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.

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://www.strongswan.org/blog/2026/03/23/strongswan-6.0.5-released.html
https://www.strongswan.org/blog/2026/03/23/strongswan-vulnerability-(cve-2026-25075).html
https://www.vulncheck.com/advisories/strongswan-eap-ttls-avp-parsing-integer-underflow
https://lists.debian.org/debian-lts-announce/2026/03/msg00016.html

Configurations

No configuration.

History

No history.

Information

Published : 2026-03-23 19:16

Updated : 2026-03-27 20:16

NVD link : CVE-2026-25075

Mitre link : CVE-2026-25075

CVE.ORG link : CVE-2026-25075

JSON object : View

Products Affected

No product.

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

CWE-476

NULL Pointer Dereference

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