CVE-2009-1957: Strongswan

Medium severity, CVSS 5.0. EPSS: 2.9% chance of exploitation in the next 30 days.

charon/sa/ike_sa.c in the charon daemon in strongSWAN before 4.3.1 allows remote attackers to cause a denial of service (NULL pointer dereference and crash) via an invalid IKE_SA_INIT request that triggers "an incomplete state," followed by a CREATE_CHILD_SA request.

Affected products

• Strongswan Strongswan: up to and including 4.3.0; version 2.0.0 only; version 2.0.1 only; version 2.0.2 only; version 2.1.0 only; version 2.1.1 only; …

Published 2009-06-08. Last modified 2026-06-16.