NULL pointer dereference in Strongswan

CVE-2026-25075

strongSwan versions 4.5.0 prior to 6.0.5 contain an integer underflow vulnerability in the EAP-TTLS AVP parser that allows unauthenticated remote attackers to cause a denial of service by sending crafted AVP data with invalid length fields during IKEv2 authentication. Attackers can exploit the failure to validate AVP length fields before subtraction to trigger excessive memory allocation or NULL pointer dereference, crashing the charon IKE daemon.

EPSS: 0.010 (59.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2026-25075?
CVE-2026-25075 is a high-severity vulnerability in Strongswan, classified under Integer Underflow. CVSS score: 7.5/10. Published 2026-03-23.
How severe is CVE-2026-25075?
High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2026-25075 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.