CVE-2026-77206: CWE-476: Null Pointer Dereference in The Libreswan Project libreswan
Description
CVE-2026-77206 is a null pointer dereference vulnerability in the Libreswan project's IKEv2 state machine, specifically in the EAP authentication handling code. This flaw can be triggered by any IKEv2 connection, even if EAP is not configured, due to a code inconsistency. A malicious IKE_AUTH packet can cause the pluto daemon to crash and restart, resulting in a denial of service. No remote code execution is possible.
CVSS v3.1
Score 7.5high
Affected software
The Libreswan Project
libreswan
pkg:github/libreswanRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Libreswan's IKEv2 state machine contains a null pointer dereference bug in the EAP handling code. The vulnerability arises from a fall-through that dereferences ike->sa.st_eap, which can be NULL. This bug can be triggered by any IKEv2 connection, regardless of EAP configuration, via a malicious IKE_AUTH packet. Exploitation leads to a crash and restart of the pluto daemon, causing denial of service. No remote code execution is achievable through this vulnerability.
Potential Impact
Successful exploitation causes the pluto daemon to crash and restart, resulting in a denial of service condition. There is no impact on confidentiality or integrity, and remote code execution is not possible.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- libreswan
- Date Reserved
- 2026-08-20T18:13:09.377Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6acea4042cdf04f656b3059d
Added to database: 10/13/2026, 21:35:00 UTC
Last enriched: 10/13/2026, 21:48:30 UTC
Last updated: 10/13/2026, 21:50:44 UTC
Views: 8
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