Vulnerability-Lookup

ubuntu-cve-2023-25136

Vulnerability from osv_ubuntu

Published

2023-02-03 06:15

Modified

2025-10-30 05:06

Summary

Details

OpenSSH server (sshd) 9.1 introduced a double-free vulnerability during options.kex_algorithms handling. This is fixed in OpenSSH 9.2. The double free can be leveraged, by an unauthenticated remote attacker in the default configuration, to jump to any location in the sshd address space. One third-party report states "remote code execution is theoretically possible."

Severity

6.5 (Medium)


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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2023-25136	REPORT
	https://www.openwall.com/lists/oss-security/2023/…	REPORT
	https://www.openwall.com/lists/oss-security/2023/…	REPORT
	https://jfrog.com/blog/openssh-pre-auth-double-fr…	REPORT
	https://www.cve.org/CVERecord?id=CVE-2023-25136	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "openssh-client",
            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.10"
          },
          {
            "binary_name": "openssh-client-hmac",
            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.10"
          },
          {
            "binary_name": "openssh-server",
            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.10"
          },
          {
            "binary_name": "openssh-server-hmac",
            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.10"
          },
          {
            "binary_name": "openssh-sftp-server",
            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.10"
          },
          {
            "binary_name": "openssh-tests",
            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.10"
          },
          {
            "binary_name": "ssh",
            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.10"
          },
          {
            "binary_name": "ssh-askpass-gnome",
            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.10"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:FIPS-updates:18.04:LTS",
        "name": "openssh",
        "purl": "pkg:deb/ubuntu/openssh@1:7.9p1-10~ubuntu18.04.fips.0.10?arch=source\u0026distro=fips-updates/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:7.9p1-10~ubuntu18.04.fips.0.1",
        "1:7.9p1-10~ubuntu18.04.fips.0.2",
        "1:7.9p1-10~ubuntu18.04.fips.0.3",
        "1:7.9p1-10~ubuntu18.04.fips.0.4",
        "1:7.9p1-10~ubuntu18.04.fips.0.5",
        "1:7.9p1-10~ubuntu18.04.fips.0.6",
        "1:7.9p1-10~ubuntu18.04.fips.0.7",
        "1:7.9p1-10~ubuntu18.04.fips.0.8",
        "1:7.9p1-10~ubuntu18.04.fips.0.9",
        "1:7.9p1-10~ubuntu18.04.fips.0.10"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "openssh-client",
            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.2"
          },
          {
            "binary_name": "openssh-client-hmac",
            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.2"
          },
          {
            "binary_name": "openssh-server",
            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.2"
          },
          {
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            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.2"
          },
          {
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            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.2"
          },
          {
            "binary_name": "openssh-tests",
            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.2"
          },
          {
            "binary_name": "ssh",
            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.2"
          },
          {
            "binary_name": "ssh-askpass-gnome",
            "binary_version": "1:7.9p1-10~ubuntu18.04.fips.0.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:FIPS:18.04:LTS",
        "name": "openssh",
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      },
      "ranges": [
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          "events": [
            {
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            }
          ],
          "type": "ECOSYSTEM"
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      ],
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        "1:7.9p1-10~ubuntu18.04.fips.0.2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "openssh-client",
            "binary_version": "1:9.6p1-3ubuntu13.14+Fips1"
          },
          {
            "binary_name": "openssh-server",
            "binary_version": "1:9.6p1-3ubuntu13.14+Fips1"
          },
          {
            "binary_name": "openssh-sftp-server",
            "binary_version": "1:9.6p1-3ubuntu13.14+Fips1"
          },
          {
            "binary_name": "openssh-tests",
            "binary_version": "1:9.6p1-3ubuntu13.14+Fips1"
          },
          {
            "binary_name": "ssh",
            "binary_version": "1:9.6p1-3ubuntu13.14+Fips1"
          },
          {
            "binary_name": "ssh-askpass-gnome",
            "binary_version": "1:9.6p1-3ubuntu13.14+Fips1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:FIPS-updates:24.04:LTS",
        "name": "openssh",
        "purl": "pkg:deb/ubuntu/openssh@1:9.6p1-3ubuntu13.14+Fips1?arch=source\u0026distro=fips-updates/noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:9.6p1-3ubuntu13.7+Fips1",
        "1:9.6p1-3ubuntu13.12+Fips1",
        "1:9.6p1-3ubuntu13.13+Fips1",
        "1:9.6p1-3ubuntu13.14+Fips1"
      ]
    }
  ],
  "aliases": [],
  "details": "OpenSSH server (sshd) 9.1 introduced a double-free vulnerability during options.kex_algorithms handling. This is fixed in OpenSSH 9.2. The double free can be leveraged, by an unauthenticated remote attacker in the default configuration, to jump to any location in the sshd address space. One third-party report states \"remote code execution is theoretically possible.\"",
  "id": "UBUNTU-CVE-2023-25136",
  "modified": "2025-10-30T05:06:42Z",
  "published": "2023-02-03T06:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2023-25136"
    },
    {
      "type": "REPORT",
      "url": "https://www.openwall.com/lists/oss-security/2023/02/02/2"
    },
    {
      "type": "REPORT",
      "url": "https://www.openwall.com/lists/oss-security/2023/02/13/1"
    },
    {
      "type": "REPORT",
      "url": "https://jfrog.com/blog/openssh-pre-auth-double-free-cve-2023-25136-writeup-and-proof-of-concept/"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2023-25136"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2023-25136"
  ],
  "withdrawn": "2025-11-25T05:07:04Z"
}

CVE-2023-25136 (GCVE-0-2023-25136)

Vulnerability from cvelistv5 – Published: 2023-02-03 00:00 – Updated: 2026-05-28 17:43

Summary

Severity

No CVSS data available.

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

n/a
CWE-415 - Double Free

Assigner

mitre

References

16 references

URL	Tags
https://ftp.openbsd.org/pub/OpenBSD/patches/7.2/c…
https://www.openwall.com/lists/oss-security/2023/…
https://bugzilla.mindrot.org/show_bug.cgi?id=3522
https://github.com/openssh/openssh-portable/commi…
https://jfrog.com/blog/openssh-pre-auth-double-fr…
https://news.ycombinator.com/item?id=34711565
http://www.openwall.com/lists/oss-security/2023/02/13/1	mailing-list
http://www.openwall.com/lists/oss-security/2023/02/22/1	mailing-list
http://www.openwall.com/lists/oss-security/2023/02/22/2	mailing-list
http://www.openwall.com/lists/oss-security/2023/02/23/3	mailing-list
http://www.openwall.com/lists/oss-security/2023/03/06/1	mailing-list
http://www.openwall.com/lists/oss-security/2023/03/09/2	mailing-list
https://security.netapp.com/advisory/ntap-2023030…
https://lists.fedoraproject.org/archives/list/pac…	vendor-advisory
https://lists.fedoraproject.org/archives/list/pac…	vendor-advisory
https://security.gentoo.org/glsa/202307-01	vendor-advisory

Show details on NVD website

JSON

To clipboard

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}

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-2023-25136

Vulnerability from osv_ubuntu

CVE-2023-25136 (GCVE-0-2023-25136)

Tags

Sightings

Nomenclature