CVE-2026-77207
Reported by libreswan · Published October 13, 2026
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.
Risk Scores
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| The Libreswan Project | libreswan | 4.7, 5.4, 5.3.3 |
| The Libreswan Project | libreswan | 4.7, 5.4, 5.3.3 |
| alpine | libreswan | 0 |
Timeline
- Oct 13, 2026 CVE Published
- Oct 14, 2026 EPSS Score
- Oct 16, 2026 EPSS Score
- Oct 16, 2026 CVE Updated
- Oct 19, 2026 EPSS Score
- Oct 21, 2026 EPSS Score
- Oct 24, 2026 EPSS Score
- Oct 25, 2026 EPSS Score
- Oct 27, 2026 Distribution Patch
- Oct 27, 2026 Security Advisory
- Oct 29, 2026 Distribution Patch
- Oct 29, 2026 Distribution Patch
References
- Libreswan Security Advisory CVE-2026-77207 vendor-advisory
- Libreswan CVE-2026-77207 Patches patch