CVE-2026-77206

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://libreswan.org/security/CVE-2026-77206/
https://libreswan.org/security/CVE-2026-77206/CVE-2026-77206.txt

Configurations

No configuration.

History

13 Oct 2026, 22:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-13 22:18

Updated : 2026-10-16 19:55

NVD link : CVE-2026-77206

Mitre link : CVE-2026-77206

CVE.ORG link : CVE-2026-77206

JSON object : View

Products Affected

No product.

CWE

CWE-476

NULL Pointer Dereference

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