7.5

CVE-2026-77206: the libreswan project libreswan NULL Pointer Dereference

CVSS: 7.5v3.1HighAwaiting analysis
AliasesDEBIAN-CVE-2026-77206UBUNTU-CVE-2026-77206
Published 13-10-2026Last modified 16-10-2026
Open JSON

Vulnerability summary

CVE-2026-77206 is a high (CVSS 7.5) NULL Pointer Dereference vulnerability in the libreswan project libreswan. EPSS estimates a 0.52% chance of exploitation in the next 30 days, higher than 42.8% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.52%
0%100%
Low · Change unavailable
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 13-10-2026
    PublishedVulnerability first disclosed.
  2. 16-10-2026
    Last modifiedVulnerability information updated.

Description

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 metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.52%

Chance of exploitation in the next 30 days

Percentile

43%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

14-10-202619-10-2026
EPSS score
0.52%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Debian1 product
  • libreswanAll versions (No fix recorded)
The libreswan project1 product
Ubuntu1 product
  • libreswanAll versions (No fix recorded)

3 vendors · 3 products

References

5 links