NULL pointer dereference in strongSwan - CVE-2026-35332
Published: September 22, 2026
Vulnerability identifier: #VU151574
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-2026-35332
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 a null-pointer dereference in libtls server-side ECDH public-value processing when handling an empty ECDH public value in a TLS client_key_exchange message before TLS 1.3. A remote attacker can send a specially crafted TLS client_key_exchange message to cause a denial of service.
The crash occurs when the TLS record ends immediately after the length byte for the empty public value.
Affected software
strongSwan
Debian Linux
Fedora
strongswan (Debian package)
strongswan
Debian Linux
Fedora
strongswan (Debian package)
strongswan
How to mitigate CVE-2026-35332
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