Integer overflow in strongSwan - CVE-2026-35333
Published: September 22, 2026
Vulnerability identifier: #VU151573
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-2026-35333
CWE-ID: CWE-190
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 integer underflow in libradius when processing crafted RADIUS attributes. A remote attacker can inject a crafted RADIUS message containing an undersized attribute to cause a denial of service.
The issue affects deployments using the eap-radius or tnc-pdp plugins; unsolicited RADIUS messages are accepted when the non-default Dynamic Authorization Extension is enabled.
Affected software
strongSwan
Debian Linux
Fedora
strongswan (Debian package)
strongswan
Debian Linux
Fedora
strongswan (Debian package)
strongswan
How to mitigate CVE-2026-35333
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