Vulnerability-Lookup

rlsa-2026:46396

Vulnerability from osv_rocky

Published

2026-07-28 06:01

Modified

2026-07-28 18:07

Summary

Important: libreswan security update

Details

Libreswan is an implementation of IPsec and IKE for Linux. IPsec is the Internet Protocol Security and uses strong cryptography to provide both authentication and encryption services. These services allow you to build secure tunnels through untrusted networks such as virtual private network (VPN).

Security Fix(es):

librenswan: IKEv1 Denial of Service via RSA-SHA1 (PKCS#1 Version 1.5 Encrypted) authentication payload (CVE-2026-50721)
librenswan: IKEv2 Denial of Service via RSA-SHA1 (PKCS#1 RSASSA-PKCS1-v1_5) authentication payload (CVE-2026-50722)
librenswan: IKEv2 Denial of Service via malformed fragmentation (CVE-2026-12413)
libreswan: badly formatted X.509 certificate can cause an assertion failure that crashes the daemon process (CVE-2026-14957)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Severity

7.5 (High)


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

Credits

Rocky Enterprise Software Foundation

Red Hat

References

URL

Type

	https://errata.rockylinux.org/RLSA-2026:46396	ADVISORY
	https://bugzilla.redhat.com/show_bug.cgi?id=2494147	REPORT
	https://bugzilla.redhat.com/show_bug.cgi?id=2494148	REPORT
	https://bugzilla.redhat.com/show_bug.cgi?id=2494149	REPORT
	https://bugzilla.redhat.com/show_bug.cgi?id=2501764	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Rocky Linux:8",
        "name": "libreswan",
        "purl": "pkg:rpm/rocky-linux/libreswan?distro=rocky-linux-8\u0026epoch=0"
      },
      "ranges": [
        {
          "database_specific": {
            "yum_repository": "AppStream"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0:4.12-2.el8_10.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "credits": [
    {
      "name": "Rocky Enterprise Software Foundation"
    },
    {
      "name": "Red Hat"
    }
  ],
  "details": "Libreswan is an implementation of IPsec and IKE for Linux. IPsec is the Internet Protocol Security and uses strong cryptography to provide both authentication and encryption services. These services allow you to build secure tunnels through untrusted networks such as virtual private network (VPN).\n\nSecurity Fix(es):\n\n* librenswan: IKEv1 Denial of Service via RSA-SHA1 (PKCS#1 Version 1.5 Encrypted) authentication payload (CVE-2026-50721)\n\n* librenswan: IKEv2 Denial of Service via RSA-SHA1 (PKCS#1 RSASSA-PKCS1-v1_5) authentication payload (CVE-2026-50722)\n\n* librenswan: IKEv2 Denial of Service via malformed fragmentation (CVE-2026-12413)\n\n* libreswan: badly formatted X.509 certificate can cause an assertion failure that crashes the daemon process (CVE-2026-14957)\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.",
  "id": "RLSA-2026:46396",
  "modified": "2026-07-28T18:07:46.161592Z",
  "published": "2026-07-28T06:01:06.284655Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://errata.rockylinux.org/RLSA-2026:46396"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2494147"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2494148"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2494149"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2501764"
    }
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Important: libreswan security update",
  "upstream": [
    "CVE-2026-12413",
    "CVE-2026-14957",
    "CVE-2026-50721",
    "CVE-2026-50722"
  ]
}

CVE-2026-12413 (GCVE-0-2026-12413)

Vulnerability from cvelistv5 – Published: 2026-07-02 21:19 – Updated: 2026-07-07 17:02

Title

IKEv2 Denial of Service via malformed fragmentation

Summary

An invalidly formatted IKEv2 fragment causes the Libreswan pluto daemon to crash and restart. Continued exploitation would cause a denial of service. The function reassemble_v2_incoming_fragments() would ignore unknown outer payloads but still store these in a fixed size array msg_digest.digest[PAYLIMIT]. An off-by-one error in the assertion PASSERT(logger, md->digest_roof < elemsof(md->digest)) causes the daemon to abort. No remote code execution is possible. Any configuration that allows IKEv2 connections that do not set fragmentation=no are vulnerable. IKEv1 is not affected.

Severity

7.5 (High)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-193 - Off-by-one Error
CWE-617 - Reachable Assertion

Assigner

libreswan

References

2 references

URL	Tags
https://libreswan.org/security/CVE-2026-12413/CVE…
https://libreswan.org/security/CVE-2026-12413/

Impacted products

1 product

Vendor	Product	Version
The Libreswan Project	libreswan	Affected: 4.6 , ≤ 5.3 (semver) Unaffected: 5.3.1 (semver)

Credits

Hu Xinyao

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-12413",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-06T18:12:21.499364Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-07T17:02:12.976Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "libreswan",
          "vendor": "The Libreswan Project",
          "versions": [
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              "lessThanOrEqual": "5.3",
              "status": "affected",
              "version": "4.6",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "5.3.1",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Hu Xinyao"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "An invalidly formatted IKEv2 fragment causes the Libreswan pluto daemon to crash and restart. Continued exploitation would cause a denial of service. The function reassemble_v2_incoming_fragments() would ignore unknown outer payloads but still store these in a fixed size array msg_digest.digest[PAYLIMIT]. An off-by-one error in the assertion PASSERT(logger, md-\u003edigest_roof \u003c elemsof(md-\u003edigest)) causes the daemon to abort. No remote code execution is possible. Any configuration that allows IKEv2 connections that do not set fragmentation=no are vulnerable. IKEv1 is not affected."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        },
        {
          "other": {
            "content": {
              "description": "Vendor-assessed severity. The daemon automatically restarts after the crash, requiring continued exploitation for sustained denial of service.",
              "value": "MEDIUM"
            },
            "type": "vendorSeverity"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-193",
              "description": "Off-by-one Error",
              "lang": "en",
              "type": "CWE"
            }
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        },
        {
          "descriptions": [
            {
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              "description": "Reachable Assertion",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-02T21:19:22.177Z",
        "orgId": "d42dc95b-23f1-4e06-9076-20753a0fb0df",
        "shortName": "libreswan"
      },
      "references": [
        {
          "name": "Libreswan Security Advisory",
          "url": "https://libreswan.org/security/CVE-2026-12413/CVE-2026-12413.txt"
        },
        {
          "name": "Libreswan CVE-2026-12413 Patches",
          "url": "https://libreswan.org/security/CVE-2026-12413/"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Upgrade to libreswan 5.3.1 or later. Patches for libreswan 4.15 and 5.3 are available at https://libreswan.org"
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2026-06-16T00:00:00.000Z",
          "value": "Libreswan notified of the issue via security@libreswan.org"
        },
        {
          "lang": "en",
          "time": "2026-06-16T00:00:00.000Z",
          "value": "Advanced notice given to supported customers and distributions"
        },
        {
          "lang": "en",
          "time": "2026-06-24T00:00:00.000Z",
          "value": "Public announcement and release of libreswan 5.3.1"
        }
      ],
      "title": "IKEv2 Denial of Service via malformed fragmentation",
      "workarounds": [
        {
          "lang": "en",
          "value": "If fragmentation is not needed, fragmentation=no can be added to all IKEv2 configurations. If fragmentation is needed, no workaround is possible and the fix needs to be applied."
        }
      ],
      "x_generator": {
        "engine": "cvelib 1.8.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "d42dc95b-23f1-4e06-9076-20753a0fb0df",
    "assignerShortName": "libreswan",
    "cveId": "CVE-2026-12413",
    "datePublished": "2026-07-02T21:19:22.177Z",
    "dateReserved": "2026-06-16T15:52:12.674Z",
    "dateUpdated": "2026-07-07T17:02:12.976Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

CVE-2026-50721 (GCVE-0-2026-50721)

Vulnerability from cvelistv5 – Published: 2026-07-02 21:44 – Updated: 2026-07-07 17:01

Title

IKEv1 Denial of Service via RSA-SHA1 (PKCS#1 Version 1.5 Encrypted) authentication payload

Summary

Libreswan, via the function RSA_authenticate_hash_signature_raw_rsa(), did not correctly verify the length of the authentication hash when the SIG payload of an IKEv1 packet was encoded using PKCS #1 RSA Encryption as per RFC 2313. A remote attacker can use a variation on the Bleichenbacher attack to forge the SIG payload when small public exponents are being used (e.g., e=3), which could lead to impersonation. Additionally, a remote attacker, by encoding a shorter than expected hash in the SIG payload, could trigger an assertion leading to denial-of-service. The daemon aborts and restarts; continued exploitation causes sustained denial of service. Remote code execution is not possible. X.509 certificate verifications of remote IKE peers are not affected.

Severity

7.5 (High)


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

8.1 (High)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-347 - Improper Verification of Cryptographic Signature
CWE-617 - Reachable Assertion

Assigner

libreswan

References

4 references

URL	Tags
https://libreswan.org/security/CVE-2026-50721/CVE…	vendor-advisory
https://libreswan.org/security/CVE-2026-50721/	patch
https://libreswan.org/security/CVE-2026-50722/CVE…	related
https://www.rfc-editor.org/rfc/rfc2313	technical-description

Impacted products

1 product

Vendor	Product	Version
The Libreswan Project	libreswan	Affected: 0 , ≤ 5.3 (semver) Unaffected: 5.3.1 (semver)

Credits

Yeonghyeon Choi Duyeong Kim Andrew Cagney (The Libreswan Team)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-50721",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-06T18:12:17.199605Z",
                "version": "2.0.3"
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              "type": "ssvc"
            }
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
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          "defaultStatus": "unaffected",
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            {
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            }
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            }
          ],
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        }
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      "exploits": [
        {
          "lang": "en",
          "value": "No known exploitation in the wild. The authentication bypass requires the target to use RSA keys with weak exponents (e=3), which have been disallowed by most cryptographic libraries for at least a decade. The denial-of-service attack is exploitable against any IKEv1 configuration using the default authby=rsasig option."
        }
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            }
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          "url": "https://libreswan.org/security/CVE-2026-50722/CVE-2026-50722.txt"
        },
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          "name": "RFC 2313 - PKCS #1: RSA Encryption Version 1.5",
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            }
          ],
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    "dateReserved": "2026-06-05T16:10:05.751Z",
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CVE-2026-50722 (GCVE-0-2026-50722)

Vulnerability from cvelistv5 – Published: 2026-07-02 21:34 – Updated: 2026-07-07 17:02

Title

IKEv2 Denial of Service via RSA-SHA1 (PKCS#1 RSASSA-PKCS1-v1_5) authentication payload

Summary

Libreswan, via the function RSA_authenticate_hash_signature_pkcs1_1_5_rsa(), did not correctly verify the DER encoding of the ASN.1 digest when the IKEv2 AUTH payload was encoded using RSASSA-PKCS1-v1_5 (RFC 8017). A remote attacker can use a variation on the Bleichenbacher attack to forge the AUTH payload when small public exponents are used (e.g., e=3), leading to impersonation. Additionally, a remote attacker, by encoding a shorter than expected hash in the AUTH payload, could trigger an assertion leading to denial-of-service. The daemon aborts and restarts; continued exploitation causes sustained denial of service. Remote code execution is not possible. X.509 certificate verifications of the remote IKE peer are not affected.

Severity

7.5 (High)


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

8.1 (High)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-347 - Improper Verification of Cryptographic Signature
CWE-617 - Reachable Assertion

Assigner

libreswan

References

4 references

URL	Tags
https://libreswan.org/security/CVE-2026-50722/CVE…	vendor-advisory
https://libreswan.org/security/CVE-2026-50722/	patch
https://libreswan.org/security/CVE-2026-50721/CVE…	related
https://www.rfc-editor.org/rfc/rfc8017	technical-description

Impacted products

1 product

Vendor	Product	Version
The Libreswan Project	libreswan	Affected: 0 , ≤ 5.3 (semver) Unaffected: 5.3.1 (semver)

Credits

Yeonghyeon Choi Duyeong Kim Andrew Cagney (The Libreswan Team)

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

Action not permitted

rlsa-2026:46396

Vulnerability from osv_rocky

CVE-2026-12413 (GCVE-0-2026-12413)

CVE-2026-50721 (GCVE-0-2026-50721)

CVE-2026-50722 (GCVE-0-2026-50722)

Tags

Sightings

Nomenclature