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

Vulnerability from cvelistv5 – Published: 2026-10-13 21:28 – Updated: 2026-10-16 15:31
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
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-16 15:14 UTC
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 

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