Null Pointer Dereference in PKCS#7 bundle with no certificates

{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-77207",
    "assignerOrgId": "d42dc95b-23f1-4e06-9076-20753a0fb0df",
    "assignerShortName": "libreswan",
    "dateUpdated": "2026-10-13T21:28:19.219Z",
    "dateReserved": "2026-08-20T18:13:09.377Z",
    "datePublished": "2026-10-13T21:28:19.219Z",
    "state": "PUBLISHED"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "d42dc95b-23f1-4e06-9076-20753a0fb0df",
        "shortName": "libreswan",
        "dateUpdated": "2026-10-13T21:28:19.219Z"
      },
      "title": "Null Pointer Dereference in PKCS#7 bundle with no certificates",
      "descriptions": [
        {
          "lang": "en",
          "value": "Libreswan has a null pointer dereference bug in the PKCS#7 handling code for IKE certificate authentication. When libreswan decodes an IKE CERT payload of type CERT_PKCS7_WRAPPED_X509, it guards the PKCS#7 blob with SEC_PKCS7ContainsCertsOrCrls() and then iterates the certificate list with SEC_PKCS7GetCertificateList(). The two NSS APIs disagree on a SignedData that carries a CRL but no certificates: ContainsCertsOrCrls() returns PR_TRUE (there is a CRL), so the guard passes, but GetCertificateList() returns NULL (there are no certificates). This causes libreswan to dereference a null pointer leading to a crash and restart. A malicious IKE_AUTH packet can trigger this bug, meaning the peer does not need to be authenticated. No remote code execution is possible. Continued exploitation can cause a denial of service."
        }
      ],
      "affected": [
        {
          "vendor": "The Libreswan Project",
          "product": "libreswan",
          "collectionURL": "https://github.com/libreswan/libreswan",
          "packageName": "libreswan",
          "programRoutines": [
            {
              "name": "decode_cert_payloads"
            }
          ],
          "repo": "https://github.com/libreswan/libreswan",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "4.7",
              "status": "affected",
              "versionType": "semver",
              "lessThanOrEqual": "5.3.2"
            },
            {
              "version": "5.4",
              "status": "affected",
              "versionType": "semver",
              "lessThanOrEqual": "5.4"
            },
            {
              "version": "5.3.3",
              "status": "unaffected",
              "versionType": "semver"
            },
            {
              "version": "5.4.1",
              "status": "unaffected",
              "versionType": "semver"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "CWE-476: Null Pointer Dereference",
              "cweId": "CWE-476",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "CWE-252: Unchecked Return Value",
              "cweId": "CWE-252",
              "type": "CWE"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://libreswan.org/security/CVE-2026-77207/CVE-2026-77207.txt",
          "name": "Libreswan Security Advisory CVE-2026-77207",
          "tags": [
            "vendor-advisory"
          ]
        },
        {
          "url": "https://libreswan.org/security/CVE-2026-77207/",
          "name": "Libreswan CVE-2026-77207 Patches",
          "tags": [
            "patch"
          ]
        }
      ],
      "impacts": [
        {
          "descriptions": [
            {
              "lang": "en",
              "value": "Denial of service via null pointer dereference in PKCS#7 certificate handling when processing malicious IKE_AUTH packets"
            }
          ]
        }
      ],
      "metrics": [
        {
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ],
          "cvssV3_1": {
            "version": "3.1",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "attackVector": "NETWORK",
            "attackComplexity": "LOW",
            "privilegesRequired": "NONE",
            "userInteraction": "NONE",
            "scope": "UNCHANGED",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH"
          }
        },
        {}
      ],
      "configurations": [
        {
          "lang": "en",
          "value": "Any server or client that accepts IKEv2 connections with certificate-based authentication is vulnerable."
        }
      ],
      "workarounds": [
        {
          "lang": "en",
          "value": "Apply the available patch or upgrade to a supported version. No configuration-based workaround is available."
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Upgrade to libreswan 5.3.3 or 5.4.1 or later. Patches are available at https://libreswan.org/security/CVE-2026-77207/"
        }
      ],
      "exploits": [
        {
          "lang": "en",
          "value": "No known exploitation in the wild. Exploitation requires sending a malicious IKE CERT payload with a PKCS#7 SignedData containing a CRL but no certificates, and does not require peer authentication."
        }
      ],
      "timeline": [
        {
          "time": "2026-08-05T00:00:00.000Z",
          "lang": "en",
          "value": "Libreswan was notified of the issue via security@libreswan.org"
        },
        {
          "time": "2026-09-24T00:00:00.000Z",
          "lang": "en",
          "value": "Advanced notice given to supported customers and distributions"
        },
        {
          "time": "2026-10-05T00:00:00.000Z",
          "lang": "en",
          "value": "Public announcement and release of libreswan 5.3.3 and 5.4.1"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Claude (Anthropic)",
          "type": "tool"
        },
        {
          "lang": "en",
          "value": "David Korczynski (ADA Logics Ltd)",
          "type": "reporter"
        }
      ],
      "taxonomyMappings": [
        {
          "taxonomyName": "ATT&CK",
          "taxonomyVersion": "15.1",
          "taxonomyRelations": [
            {
              "taxonomyId": "T1499.004",
              "relationshipName": "maps to",
              "relationshipValue": "Application or System Exploitation (DoS)"
            }
          ]
        }
      ]
    }
  }
}