CVE-2026-77207 (GCVE-0-2026-77207)
Vulnerability from cvelistv5
Published
2026-10-13 21:28
Modified
2026-10-16 15:31
CWE
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.
Impacted products
Vendor Product Version
The Libreswan Project libreswan Version: 4.7   ≤ 5.3.2
Version: 5.4   ≤ 5.4
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Show details on NVD website


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          "lang": "en",
          "time": "2026-08-05T00:00:00.000Z",
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Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.


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