Vulnerability-Lookup

ubuntu-cve-2026-33603

Vulnerability from osv_ubuntu

Published

2026-05-12 14:17

Modified

2026-06-02 15:30

Summary

Details

Attacker can use a specially crafted base64 exchange between Dovecot and Client to fake SCRAM TLS channel binding. This requires that the attacker is able to position itself between Dovecot and the client connection. If successful, the attacker can eavesdrop communications between Dovecot and client as MITM proxy. Install fixed version. No publicly available exploits are known.

Severity

6.8 (Medium)


                    
                      CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

5.3 (Medium)


                    
                      CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-33603	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-33603	REPORT
	https://www.openwall.com/lists/oss-security/2026/…	REPORT
	https://ubuntu.com/security/notices/USN-8365-1	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "dovecot-core",
            "binary_version": "1:2.2.9-1ubuntu2.6+esm4"
          },
          {
            "binary_name": "dovecot-gssapi",
            "binary_version": "1:2.2.9-1ubuntu2.6+esm4"
          },
          {
            "binary_name": "dovecot-imapd",
            "binary_version": "1:2.2.9-1ubuntu2.6+esm4"
          },
          {
            "binary_name": "dovecot-ldap",
            "binary_version": "1:2.2.9-1ubuntu2.6+esm4"
          },
          {
            "binary_name": "dovecot-lmtpd",
            "binary_version": "1:2.2.9-1ubuntu2.6+esm4"
          },
          {
            "binary_name": "dovecot-managesieved",
            "binary_version": "1:2.2.9-1ubuntu2.6+esm4"
          },
          {
            "binary_name": "dovecot-mysql",
            "binary_version": "1:2.2.9-1ubuntu2.6+esm4"
          },
          {
            "binary_name": "dovecot-pgsql",
            "binary_version": "1:2.2.9-1ubuntu2.6+esm4"
          },
          {
            "binary_name": "dovecot-pop3d",
            "binary_version": "1:2.2.9-1ubuntu2.6+esm4"
          },
          {
            "binary_name": "dovecot-sieve",
            "binary_version": "1:2.2.9-1ubuntu2.6+esm4"
          },
          {
            "binary_name": "dovecot-solr",
            "binary_version": "1:2.2.9-1ubuntu2.6+esm4"
          },
          {
            "binary_name": "dovecot-sqlite",
            "binary_version": "1:2.2.9-1ubuntu2.6+esm4"
          },
          {
            "binary_name": "mail-stack-delivery",
            "binary_version": "1:2.2.9-1ubuntu2.6+esm4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "dovecot",
        "purl": "pkg:deb/ubuntu/dovecot@1:2.2.9-1ubuntu2.6+esm4?arch=source\u0026distro=esm-infra-legacy/trusty"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:2.1.7-7ubuntu3",
        "1:2.2.9-1ubuntu1",
        "1:2.2.9-1ubuntu2",
        "1:2.2.9-1ubuntu2.1",
        "1:2.2.9-1ubuntu2.3",
        "1:2.2.9-1ubuntu2.4",
        "1:2.2.9-1ubuntu2.5",
        "1:2.2.9-1ubuntu2.6",
        "1:2.2.9-1ubuntu2.6+esm1",
        "1:2.2.9-1ubuntu2.6+esm2",
        "1:2.2.9-1ubuntu2.6+esm3",
        "1:2.2.9-1ubuntu2.6+esm4"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "dovecot-core",
            "binary_version": "1:2.2.22-1ubuntu2.14"
          },
          {
            "binary_name": "dovecot-gssapi",
            "binary_version": "1:2.2.22-1ubuntu2.14"
          },
          {
            "binary_name": "dovecot-imapd",
            "binary_version": "1:2.2.22-1ubuntu2.14"
          },
          {
            "binary_name": "dovecot-ldap",
            "binary_version": "1:2.2.22-1ubuntu2.14"
          },
          {
            "binary_name": "dovecot-lmtpd",
            "binary_version": "1:2.2.22-1ubuntu2.14"
          },
          {
            "binary_name": "dovecot-lucene",
            "binary_version": "1:2.2.22-1ubuntu2.14"
          },
          {
            "binary_name": "dovecot-managesieved",
            "binary_version": "1:2.2.22-1ubuntu2.14"
          },
          {
            "binary_name": "dovecot-mysql",
            "binary_version": "1:2.2.22-1ubuntu2.14"
          },
          {
            "binary_name": "dovecot-pgsql",
            "binary_version": "1:2.2.22-1ubuntu2.14"
          },
          {
            "binary_name": "dovecot-pop3d",
            "binary_version": "1:2.2.22-1ubuntu2.14"
          },
          {
            "binary_name": "dovecot-sieve",
            "binary_version": "1:2.2.22-1ubuntu2.14"
          },
          {
            "binary_name": "dovecot-solr",
            "binary_version": "1:2.2.22-1ubuntu2.14"
          },
          {
            "binary_name": "dovecot-sqlite",
            "binary_version": "1:2.2.22-1ubuntu2.14"
          },
          {
            "binary_name": "mail-stack-delivery",
            "binary_version": "1:2.2.22-1ubuntu2.14"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:16.04:LTS",
        "name": "dovecot",
        "purl": "pkg:deb/ubuntu/dovecot@1:2.2.22-1ubuntu2.14?arch=source\u0026distro=xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:2.2.18-2ubuntu2",
        "1:2.2.22-1ubuntu1",
        "1:2.2.22-1ubuntu2",
        "1:2.2.22-1ubuntu2.1",
        "1:2.2.22-1ubuntu2.2",
        "1:2.2.22-1ubuntu2.3",
        "1:2.2.22-1ubuntu2.4",
        "1:2.2.22-1ubuntu2.6",
        "1:2.2.22-1ubuntu2.7",
        "1:2.2.22-1ubuntu2.8",
        "1:2.2.22-1ubuntu2.9",
        "1:2.2.22-1ubuntu2.10",
        "1:2.2.22-1ubuntu2.11",
        "1:2.2.22-1ubuntu2.12",
        "1:2.2.22-1ubuntu2.13",
        "1:2.2.22-1ubuntu2.14"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "dovecot-core",
            "binary_version": "1:2.2.33.2-1ubuntu4.8"
          },
          {
            "binary_name": "dovecot-gssapi",
            "binary_version": "1:2.2.33.2-1ubuntu4.8"
          },
          {
            "binary_name": "dovecot-imapd",
            "binary_version": "1:2.2.33.2-1ubuntu4.8"
          },
          {
            "binary_name": "dovecot-ldap",
            "binary_version": "1:2.2.33.2-1ubuntu4.8"
          },
          {
            "binary_name": "dovecot-lmtpd",
            "binary_version": "1:2.2.33.2-1ubuntu4.8"
          },
          {
            "binary_name": "dovecot-managesieved",
            "binary_version": "1:2.2.33.2-1ubuntu4.8"
          },
          {
            "binary_name": "dovecot-mysql",
            "binary_version": "1:2.2.33.2-1ubuntu4.8"
          },
          {
            "binary_name": "dovecot-pgsql",
            "binary_version": "1:2.2.33.2-1ubuntu4.8"
          },
          {
            "binary_name": "dovecot-pop3d",
            "binary_version": "1:2.2.33.2-1ubuntu4.8"
          },
          {
            "binary_name": "dovecot-sieve",
            "binary_version": "1:2.2.33.2-1ubuntu4.8"
          },
          {
            "binary_name": "dovecot-solr",
            "binary_version": "1:2.2.33.2-1ubuntu4.8"
          },
          {
            "binary_name": "dovecot-sqlite",
            "binary_version": "1:2.2.33.2-1ubuntu4.8"
          },
          {
            "binary_name": "mail-stack-delivery",
            "binary_version": "1:2.2.33.2-1ubuntu4.8"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "dovecot",
        "purl": "pkg:deb/ubuntu/dovecot@1:2.2.33.2-1ubuntu4.8?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:2.2.27-3ubuntu1",
        "1:2.2.33.2-1ubuntu1",
        "1:2.2.33.2-1ubuntu2",
        "1:2.2.33.2-1ubuntu3",
        "1:2.2.33.2-1ubuntu4",
        "1:2.2.33.2-1ubuntu4.1",
        "1:2.2.33.2-1ubuntu4.2",
        "1:2.2.33.2-1ubuntu4.3",
        "1:2.2.33.2-1ubuntu4.4",
        "1:2.2.33.2-1ubuntu4.5",
        "1:2.2.33.2-1ubuntu4.6",
        "1:2.2.33.2-1ubuntu4.7",
        "1:2.2.33.2-1ubuntu4.8"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "dovecot-auth-lua",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          },
          {
            "binary_name": "dovecot-core",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          },
          {
            "binary_name": "dovecot-gssapi",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          },
          {
            "binary_name": "dovecot-imapd",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          },
          {
            "binary_name": "dovecot-ldap",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          },
          {
            "binary_name": "dovecot-lmtpd",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          },
          {
            "binary_name": "dovecot-lucene",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          },
          {
            "binary_name": "dovecot-managesieved",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          },
          {
            "binary_name": "dovecot-mysql",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          },
          {
            "binary_name": "dovecot-pgsql",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          },
          {
            "binary_name": "dovecot-pop3d",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          },
          {
            "binary_name": "dovecot-sieve",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          },
          {
            "binary_name": "dovecot-solr",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          },
          {
            "binary_name": "dovecot-sqlite",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          },
          {
            "binary_name": "dovecot-submissiond",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          },
          {
            "binary_name": "mail-stack-delivery",
            "binary_version": "1:2.3.7.2-1ubuntu3.7"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "dovecot",
        "purl": "pkg:deb/ubuntu/dovecot@1:2.3.7.2-1ubuntu3.7?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:2.3.4.1-5ubuntu3",
        "1:2.3.7.2-1ubuntu1",
        "1:2.3.7.2-1ubuntu2",
        "1:2.3.7.2-1ubuntu3",
        "1:2.3.7.2-1ubuntu3.1",
        "1:2.3.7.2-1ubuntu3.2",
        "1:2.3.7.2-1ubuntu3.3",
        "1:2.3.7.2-1ubuntu3.4",
        "1:2.3.7.2-1ubuntu3.5",
        "1:2.3.7.2-1ubuntu3.6",
        "1:2.3.7.2-1ubuntu3.7"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "dovecot-auth-lua",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-core",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-gssapi",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-imapd",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-ldap",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-lmtpd",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-lucene",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-managesieved",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-mysql",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-pgsql",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-pop3d",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-sieve",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-solr",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-sqlite",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-submissiond",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "dovecot",
        "purl": "pkg:deb/ubuntu/dovecot@1:2.3.16+dfsg1-3ubuntu2.9?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:2.3.16+dfsg1-3ubuntu2.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:2.3.13+dfsg1-1ubuntu3",
        "1:2.3.16+dfsg1-3ubuntu1",
        "1:2.3.16+dfsg1-3ubuntu2",
        "1:2.3.16+dfsg1-3ubuntu2.1",
        "1:2.3.16+dfsg1-3ubuntu2.2",
        "1:2.3.16+dfsg1-3ubuntu2.4",
        "1:2.3.16+dfsg1-3ubuntu2.6",
        "1:2.3.16+dfsg1-3ubuntu2.7",
        "1:2.3.16+dfsg1-3ubuntu2.8"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "dovecot-auth-lua",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-core",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-gssapi",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-imapd",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-ldap",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-lmtpd",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-managesieved",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-mysql",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-pgsql",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-pop3d",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-sieve",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-solr",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-sqlite",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-submissiond",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "dovecot",
        "purl": "pkg:deb/ubuntu/dovecot@1:2.3.21+dfsg1-2ubuntu6.5?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:2.3.21+dfsg1-2ubuntu6.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:2.3.20+dfsg1-1ubuntu3",
        "1:2.3.21+dfsg1-2ubuntu1",
        "1:2.3.21+dfsg1-2ubuntu2",
        "1:2.3.21+dfsg1-2ubuntu4",
        "1:2.3.21+dfsg1-2ubuntu5",
        "1:2.3.21+dfsg1-2ubuntu6",
        "1:2.3.21+dfsg1-2ubuntu6.1",
        "1:2.3.21+dfsg1-2ubuntu6.2",
        "1:2.3.21+dfsg1-2ubuntu6.3",
        "1:2.3.21+dfsg1-2ubuntu6.4"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "dovecot-auth-lua",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-core",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-flatcurve",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-gssapi",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-imapd",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-ldap",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-lmtpd",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-managesieved",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-mysql",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-pgsql",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-pop3d",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-sieve",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-solr",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-sqlite",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-submissiond",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "dovecot",
        "purl": "pkg:deb/ubuntu/dovecot@1:2.4.1+dfsg1-5ubuntu4.2?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:2.4.1+dfsg1-5ubuntu4.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:2.3.21.1+dfsg1-1ubuntu2",
        "1:2.4.1+dfsg1-5ubuntu1",
        "1:2.4.1+dfsg1-5ubuntu3",
        "1:2.4.1+dfsg1-5ubuntu4",
        "1:2.4.1+dfsg1-5ubuntu4.1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "dovecot-auth-lua",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-core",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-flatcurve",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-gssapi",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-imapd",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-ldap",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-lmtpd",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-managesieved",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-mysql",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-pgsql",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-pop3d",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-sieve",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-solr",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-sqlite",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-submissiond",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "dovecot",
        "purl": "pkg:deb/ubuntu/dovecot@1:2.4.2+dfsg1-3ubuntu2.1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:2.4.2+dfsg1-3ubuntu2.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:2.4.1+dfsg1-5ubuntu4",
        "1:2.4.1+dfsg1-5ubuntu5",
        "1:2.4.2+dfsg1-3ubuntu1",
        "1:2.4.2+dfsg1-3ubuntu2"
      ]
    }
  ],
  "aliases": [],
  "details": "Attacker can use a specially crafted base64 exchange between Dovecot and Client to fake SCRAM TLS channel binding. This requires that the attacker is able to position itself between Dovecot and the client connection. If successful, the attacker can eavesdrop communications between Dovecot and client as MITM proxy. Install fixed version. No publicly available exploits are known.",
  "id": "UBUNTU-CVE-2026-33603",
  "modified": "2026-06-02T15:30:35Z",
  "published": "2026-05-12T14:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-33603"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-33603"
    },
    {
      "type": "REPORT",
      "url": "https://www.openwall.com/lists/oss-security/2026/05/12/6"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8365-1"
    }
  ],
  "related": [
    "USN-8365-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-33603"
  ]
}

CVE-2026-33603 (GCVE-0-2026-33603)

Vulnerability from cvelistv5 – Published: 2026-05-12 13:28 – Updated: 2026-05-12 15:08

Summary

Severity

6.8 (Medium)


                        
                          CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator (v2.0.3)

CWE

CWE-99 - Improper Control of Resource Identifiers ('Resource Injection')

Assigner

References

1 reference

URL	Tags
https://documentation.open-xchange.com/dovecot/se…	vendor-advisory

Impacted products

1 product

Vendor	Product	Version
Open-Xchange GmbH	OX Dovecot Pro	Affected: 0 , ≤ 3.1.0 (semver) Affected: 0 , ≤ 2.4.0 (semver)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-33603",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-12T15:07:52.503674Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-12T15:08:00.334Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "modules": [
            "core"
          ],
          "product": "OX Dovecot Pro",
          "vendor": "Open-Xchange GmbH",
          "versions": [
            {
              "lessThanOrEqual": "3.1.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "2.4.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Attacker can use a specially crafted base64 exchange between Dovecot and Client to fake SCRAM TLS channel binding. This requires that the attacker is able to position itself between Dovecot and the client connection. If successful, the attacker can eavesdrop communications between Dovecot and client as MITM proxy. Install fixed version. No publicly available exploits are known."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "ADJACENT_NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.8,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-99",
              "description": "Improper Control of Resource Identifiers (\u0027Resource Injection\u0027)",
              "lang": "en",
              "type": "cwe"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-12T13:39:01.528Z",
        "orgId": "8ce71d90-2354-404b-a86e-bec2cc4e6981",
        "shortName": "OX"
      },
      "references": [
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0002.json"
        }
      ],
      "source": {
        "defect": "DOV-9030",
        "discovery": "EXTERNAL"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "8ce71d90-2354-404b-a86e-bec2cc4e6981",
    "assignerShortName": "OX",
    "cveId": "CVE-2026-33603",
    "datePublished": "2026-05-12T13:28:44.802Z",
    "dateReserved": "2026-03-23T12:58:38.266Z",
    "dateUpdated": "2026-05-12T15:08:00.334Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

usn-8365-1

Vulnerability from osv_ubuntu

Published

2026-06-02 12:42

Modified

2026-06-30 15:55

Summary

dovecot vulnerabilities

Details

It was discovered that Dovecot incorrectly treated some variable expansion pipelines as safe in authentication filters. An attacker could possibly use this issue to perform SQL or LDAP injection attacks. This issue only affected Ubuntu 25.10 and Ubuntu 26.04 LTS. (CVE-2026-27851)

It was discovered that Dovecot incorrectly verified SCRAM TLS channel binding in certain base64 exchanges. A remote attacker could possibly use this issue to obtain sensitive information in a machine-in-the-middle attack. (CVE-2026-33603)

It was discovered that Dovecot incorrectly enforced Sieve script CPU limits. An attacker could possibly use this issue to cause Dovecot to use excessive resources, leading to a denial of service. (CVE-2026-40016)

It was discovered that Dovecot incorrectly handled certain IMAP SETACL commands. An attacker could possibly use this issue to spam folders to other users. (CVE-2026-40020)

It was discovered that Dovecot incorrectly handled excessive IMAP bracing. An attacker could possibly use this issue to cause Dovecot to use excessive resources, leading to a denial of service. (CVE-2026-42006)

References

URL

Type

	https://ubuntu.com/security/notices/USN-8365-1	ADVISORY
	https://ubuntu.com/security/CVE-2026-27851	REPORT
	https://ubuntu.com/security/CVE-2026-33603	REPORT
	https://ubuntu.com/security/CVE-2026-40016	REPORT
	https://ubuntu.com/security/CVE-2026-40020	REPORT
	https://ubuntu.com/security/CVE-2026-42006	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-33603",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-40016",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-40020",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-42006",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:22.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "dovecot-auth-lua",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-core",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-gssapi",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-imapd",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-ldap",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-lmtpd",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-lucene",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-managesieved",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-mysql",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-pgsql",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-pop3d",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-sieve",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-solr",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-sqlite",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          },
          {
            "binary_name": "dovecot-submissiond",
            "binary_version": "1:2.3.16+dfsg1-3ubuntu2.9"
          }
        ]
      },
      "package": {
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        "name": "dovecot",
        "purl": "pkg:deb/ubuntu/dovecot@1:2.3.16+dfsg1-3ubuntu2.9?arch=source\u0026distro=jammy"
      },
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        "1:2.3.16+dfsg1-3ubuntu2.1",
        "1:2.3.16+dfsg1-3ubuntu2.2",
        "1:2.3.16+dfsg1-3ubuntu2.4",
        "1:2.3.16+dfsg1-3ubuntu2.6",
        "1:2.3.16+dfsg1-3ubuntu2.7",
        "1:2.3.16+dfsg1-3ubuntu2.8"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-33603",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-40016",
              "severity": [
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                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
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            {
              "id": "CVE-2026-40020",
              "severity": [
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                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
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            {
              "id": "CVE-2026-42006",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
                  "type": "CVSS_V3"
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                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:24.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "dovecot-auth-lua",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-core",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-gssapi",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-imapd",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-ldap",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-lmtpd",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-managesieved",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-mysql",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-pgsql",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-pop3d",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-sieve",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-solr",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-sqlite",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          },
          {
            "binary_name": "dovecot-submissiond",
            "binary_version": "1:2.3.21+dfsg1-2ubuntu6.5"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "dovecot",
        "purl": "pkg:deb/ubuntu/dovecot@1:2.3.21+dfsg1-2ubuntu6.5?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:2.3.21+dfsg1-2ubuntu6.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:2.3.20+dfsg1-1ubuntu3",
        "1:2.3.21+dfsg1-2ubuntu1",
        "1:2.3.21+dfsg1-2ubuntu2",
        "1:2.3.21+dfsg1-2ubuntu4",
        "1:2.3.21+dfsg1-2ubuntu5",
        "1:2.3.21+dfsg1-2ubuntu6",
        "1:2.3.21+dfsg1-2ubuntu6.1",
        "1:2.3.21+dfsg1-2ubuntu6.2",
        "1:2.3.21+dfsg1-2ubuntu6.3",
        "1:2.3.21+dfsg1-2ubuntu6.4"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-27851",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-33603",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-40016",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-40020",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-42006",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:25.10"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "dovecot-auth-lua",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-core",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-flatcurve",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-gssapi",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-imapd",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-ldap",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-lmtpd",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-managesieved",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-mysql",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-pgsql",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-pop3d",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-sieve",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-solr",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-sqlite",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          },
          {
            "binary_name": "dovecot-submissiond",
            "binary_version": "1:2.4.1+dfsg1-5ubuntu4.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "dovecot",
        "purl": "pkg:deb/ubuntu/dovecot@1:2.4.1+dfsg1-5ubuntu4.2?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:2.4.1+dfsg1-5ubuntu4.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:2.3.21.1+dfsg1-1ubuntu2",
        "1:2.4.1+dfsg1-5ubuntu1",
        "1:2.4.1+dfsg1-5ubuntu3",
        "1:2.4.1+dfsg1-5ubuntu4",
        "1:2.4.1+dfsg1-5ubuntu4.1"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-27851",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-33603",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-40016",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-40020",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-42006",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:26.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "dovecot-auth-lua",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-core",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-flatcurve",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-gssapi",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-imapd",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-ldap",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-lmtpd",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-managesieved",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-mysql",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-pgsql",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-pop3d",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-sieve",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-solr",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-sqlite",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          },
          {
            "binary_name": "dovecot-submissiond",
            "binary_version": "1:2.4.2+dfsg1-3ubuntu2.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "dovecot",
        "purl": "pkg:deb/ubuntu/dovecot@1:2.4.2+dfsg1-3ubuntu2.1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:2.4.2+dfsg1-3ubuntu2.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:2.4.1+dfsg1-5ubuntu4",
        "1:2.4.1+dfsg1-5ubuntu5",
        "1:2.4.2+dfsg1-3ubuntu1",
        "1:2.4.2+dfsg1-3ubuntu2"
      ]
    }
  ],
  "aliases": [],
  "details": "It was discovered that Dovecot incorrectly treated some variable expansion\npipelines as safe in authentication filters. An attacker could possibly use\nthis issue to perform SQL or LDAP injection attacks. This issue only\naffected Ubuntu 25.10 and Ubuntu 26.04 LTS. (CVE-2026-27851)\n\nIt was discovered that Dovecot incorrectly verified SCRAM TLS channel\nbinding in certain base64 exchanges. A remote attacker could possibly use\nthis issue to obtain sensitive information in a machine-in-the-middle\nattack. (CVE-2026-33603)\n\nIt was discovered that Dovecot incorrectly enforced Sieve script CPU\nlimits. An attacker could possibly use this issue to cause Dovecot to use\nexcessive resources, leading to a denial of service. (CVE-2026-40016)\n\nIt was discovered that Dovecot incorrectly handled certain IMAP SETACL\ncommands. An attacker could possibly use this issue to spam folders to\nother users. (CVE-2026-40020)\n\nIt was discovered that Dovecot incorrectly handled excessive IMAP bracing.\nAn attacker could possibly use this issue to cause Dovecot to use excessive\nresources, leading to a denial of service. (CVE-2026-42006)",
  "id": "USN-8365-1",
  "modified": "2026-06-30T15:55:20Z",
  "published": "2026-06-02T12:42:17Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8365-1"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-27851"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-33603"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-40016"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-40020"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-42006"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "dovecot vulnerabilities",
  "upstream": [
    "UBUNTU-CVE-2026-27851",
    "UBUNTU-CVE-2026-33603",
    "UBUNTU-CVE-2026-40016",
    "UBUNTU-CVE-2026-40020",
    "UBUNTU-CVE-2026-42006"
  ]
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

ubuntu-cve-2026-33603

Vulnerability from osv_ubuntu

CVE-2026-33603 (GCVE-0-2026-33603)

usn-8365-1

Vulnerability from osv_ubuntu

Tags

Sightings

Nomenclature