NULL pointer dereference in strongSwan - CVE-2026-35329
Published: September 22, 2026
Vulnerability identifier: #VU151577
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-35329
CWE-ID: CWE-476
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to missing zero-length input validation in the PKCS#5 implementation in libstrongswan and the PKCS#7 implementation in the pkcs7 plugin when processing empty encrypted PKCS#7 or PKCS#5 structures. A remote attacker can supply an empty encrypted structure to trigger a null-pointer dereference and cause a crash.
Remote exploitation is possible via IKEv1 CERT payloads containing PKCS#7-wrapped X.509 certificates.
Affected software
strongSwan
Debian Linux
Fedora
strongswan (Debian package)
strongswan
Debian Linux
Fedora
strongswan (Debian package)
strongswan
How to mitigate CVE-2026-35329
Install security update from vendor's website.
strongSwan - update to 6.0.6
strongswan (Debian package) - addressed in versions 5.9.8-5+deb12u4, 6.0.1-6+deb13u5
strongswan - addressed in versions 6.0.6-1.el8, 6.0.6-1.el9, 6.0.6-1.el10_3, 6.0.6-2.fc44, 6.0.6-3.fc43, 6.0.7-2.fc43
strongswan (Debian package) - addressed in versions 5.9.8-5+deb12u4, 6.0.1-6+deb13u5
strongswan - addressed in versions 6.0.6-1.el8, 6.0.6-1.el9, 6.0.6-1.el10_3, 6.0.6-2.fc44, 6.0.6-3.fc43, 6.0.7-2.fc43