VDB
CVE-2026-77206
CVE-2026-77206
PUBLISHED
CVSS 7.5 HIGH
Reported by libreswan · Published October 13, 2026
Libreswan's IKEv2 state machine has a null pointer dereference bug in the EAP handling code for authentication. As a result of inconsistency within the IKEv2 state machine code, this bug can be triggered by any IKEv2 connection, even if EAP is not configured at all. The error is caused by a fall-through where it incorrectly dereferences ike->sa.st_eap which is NULL. A malicious IKE_AUTH packet can trigger this bug, meaning the peer does not need to be authenticated. The bug results in a crash and restart of the pluto daemon. No remote code execution is possible. Continued exploitation can cause a denial of service.
Risk Scores
CVSS 3.1
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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 20, 2026 EPSS Score
- Oct 21, 2026 EPSS Score
- Oct 24, 2026 EPSS Score
- Oct 25, 2026 EPSS Score
- Oct 27, 2026 EPSS Score
- Oct 27, 2026 Distribution Patch
- Oct 27, 2026 Security Advisory
- Oct 29, 2026 EPSS Score
References
- Libreswan Security Advisory CVE-2026-77206 vendor-advisory
- Libreswan CVE-2026-77206 Patches patch