Improper Verification of Cryptographic Signature in gosaml2 - #VU128391
Published: April 28, 2026
Vulnerability identifier: #VU128391
CSH Severity: Medium
CVSSv4.0: 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/E:U/U:Green
CVE-ID: N/A
CWE-ID: CWE-347
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
gosaml2
gosaml2
Software vendor:
Russell Haering
Russell Haering
Description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to improper verification of cryptographic signature in ValidateEncodedLogoutRequestPOST when processing SAML LogoutRequest messages sent to the single logout endpoint. A remote attacker can send a specially crafted unsigned logout request to cause a denial of service.
Unsigned requests may be accepted even when signature validation is configured to be enforced.
Remediation
Install security update from vendor's website.