CVE-2026-77207 (GCVE-0-2026-77207)

Vulnerability from cvelistv5 – Published: 2026-10-13 21:28 – Updated: 2026-10-13 21:28
VLAI
Title
Null Pointer Dereference in PKCS#7 bundle with no certificates
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
Assigner
libreswan CNA under the mitre root
CNA scorecard – unranked: 8 records in the last 180 days, 10 needed details
References
Impacted products
Vendor Product Version CPE status
The Libreswan Project libreswan Affected: 4.7 , ≤ 5.3.2 (semver)
Affected: 5.4 , ≤ 5.4 (semver)
Unaffected: 5.3.3 (semver)
Unaffected: 5.4.1 (semver)
guessed Create a notification for this product.
Credits
Claude (Anthropic) David Korczynski (ADA Logics Ltd)
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "collectionURL": "https://github.com/libreswan/libreswan",
          "defaultStatus": "unaffected",
          "packageName": "libreswan",
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          "programRoutines": [
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            }
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          "versions": [
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              "version": "4.7",
              "versionType": "semver"
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              "version": "5.4",
              "versionType": "semver"
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            {
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              "version": "5.3.3",
              "versionType": "semver"
            },
            {
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              "version": "5.4.1",
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            }
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      ],
      "configurations": [
        {
          "lang": "en",
          "value": "Any server or client that accepts IKEv2 connections with certificate-based authentication is vulnerable."
        }
      ],
      "credits": [
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          "lang": "en",
          "type": "tool",
          "value": "Claude (Anthropic)"
        },
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          "type": "reporter",
          "value": "David Korczynski (ADA Logics Ltd)"
        }
      ],
      "descriptions": [
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          "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."
        }
      ],
      "exploits": [
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          "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."
        }
      ],
      "impacts": [
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          "descriptions": [
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              "lang": "en",
              "value": "Denial of service via null pointer dereference in PKCS#7 certificate handling when processing malicious IKE_AUTH packets"
            }
          ]
        }
      ],
      "metrics": [
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            "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"
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          "scenarios": [
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              "value": "GENERAL"
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        },
        {
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            "content": {
              "description": "Vendor-assessed severity: Medium. Exploitation does not require authentication, but the daemon automatically restarts after the crash, requiring continued exploitation for sustained denial of service.",
              "value": "MEDIUM"
            },
            "type": "vendorSeverity"
          }
        }
      ],
      "problemTypes": [
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              "description": "CWE-476: Null Pointer Dereference",
              "lang": "en",
              "type": "CWE"
            }
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        },
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          "descriptions": [
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              "description": "CWE-252: Unchecked Return Value",
              "lang": "en",
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      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-13T21:28:19.219Z",
        "orgId": "d42dc95b-23f1-4e06-9076-20753a0fb0df",
        "shortName": "libreswan"
      },
      "references": [
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          "name": "Libreswan Security Advisory CVE-2026-77207",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://libreswan.org/security/CVE-2026-77207/CVE-2026-77207.txt"
        },
        {
          "name": "Libreswan CVE-2026-77207 Patches",
          "tags": [
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          ],
          "url": "https://libreswan.org/security/CVE-2026-77207/"
        }
      ],
      "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/"
        }
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        "discovery": "EXTERNAL"
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      "taxonomyMappings": [
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          "taxonomyName": "ATT\u0026CK",
          "taxonomyRelations": [
            {
              "relationshipName": "maps to",
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      "timeline": [
        {
          "lang": "en",
          "time": "2026-08-05T00:00:00.000Z",
          "value": "Libreswan was notified of the issue via security@libreswan.org"
        },
        {
          "lang": "en",
          "time": "2026-09-24T00:00:00.000Z",
          "value": "Advanced notice given to supported customers and distributions"
        },
        {
          "lang": "en",
          "time": "2026-10-05T00:00:00.000Z",
          "value": "Public announcement and release of libreswan 5.3.3 and 5.4.1"
        }
      ],
      "title": "Null Pointer Dereference in PKCS#7 bundle with no certificates",
      "workarounds": [
        {
          "lang": "en",
          "value": "Apply the available patch or upgrade to a supported version. No configuration-based workaround is available."
        }
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      "x_generator": {
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      }
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  },
  "cveMetadata": {
    "assignerOrgId": "d42dc95b-23f1-4e06-9076-20753a0fb0df",
    "assignerShortName": "libreswan",
    "cveId": "CVE-2026-77207",
    "datePublished": "2026-10-13T21:28:19.219Z",
    "dateReserved": "2026-08-20T18:13:09.377Z",
    "dateUpdated": "2026-10-13T21:28:19.219Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
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            "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."
          }
        ],
        "id": "CVE-2026-77207",
        "lastModified": "2026-10-13T22:18:26.040",
        "metrics": {
          "cvssMetricV31": [
            {
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                "attackVector": "NETWORK",
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                "baseScore": 7.5,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "NONE",
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                "privilegesRequired": "NONE",
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              "source": "d42dc95b-23f1-4e06-9076-20753a0fb0df",
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            "url": "https://libreswan.org/security/CVE-2026-77207/"
          },
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            "source": "d42dc95b-23f1-4e06-9076-20753a0fb0df",
            "url": "https://libreswan.org/security/CVE-2026-77207/CVE-2026-77207.txt"
          }
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        "vulnStatus": "Received",
        "weaknesses": [
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            "type": "Secondary"
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      "cve": "CVE-2026-77207",
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      "product_status:known_affected": "12",
      "product_status:known_not_affected": "3",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "libreswan: Null Pointer Dereference in PKCS#7 bundle with no CERTS",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-77207.json",
      "version": "3"
    }
  }
}



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