Packagist/simplesamlphp/saml2-legacy CVE-2025-27773: high 8.6, EPSS 0.41%

The SimpleSAMLphp SAML2 library incorrectly verifies signatures for HTTP-Redirect binding

Action: Upgrade simplesamlphp/saml2-legacy to 4.17.0 or later.

composer require simplesamlphp/saml2-legacy:4.17.0

Affected

Fixed versions

Sources

• osv: GHSA-46r4-f8gj-xg56#Packagist/simplesamlphp/saml2-legacy
• https://github.com/simplesamlphp/saml2/security/advisories/GHSA-46r4-f8gj-xg56
• https://nvd.nist.gov/vuln/detail/CVE-2025-27773
• https://github.com/simplesamlphp/saml2/commit/7867d6099dc7f31bed1ea10e5bea159c5623d2a0
• https://github.com/simplesamlphp/saml2
• https://github.com/simplesamlphp/saml2/blob/9545abd0d9d48388f2fa00469c5c1e0294f0303e/src/SAML2/HTTPRedirect.php#L104-L113
• https://github.com/simplesamlphp/saml2/blob/9545abd0d9d48388f2fa00469c5c1e0294f0303e/src/SAML2/HTTPRedirect.php#L178-L217
• https://lists.debian.org/debian-lts-announce/2025/05/msg00013.html

CVE-2025-27773 · published 2025-03-11T19:23:22Z · modified 2026-09-10T03:50:56.811522448Z · JSON