CVE-2025-27773: The SimpleSAMLphp SAML2 library incorrectly verifies signatures for HTTP-Redirect binding

CVE-2025-27773 · Severity: low · CVSS 3.1 · Published 2025-03-11

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

Technologies: simplesamlphp/saml2 (Packagist), simplesamlphp/saml2-legacy (Packagist). Vendors: Packagist.

Quick answers

Is CVE-2025-27773 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2025-27773 being exploited in the wild.
How severe is CVE-2025-27773?
Low severity, with a CVSS score of 3.1, published 11 March 2025.
Which products and versions are affected?
simplesamlphp/saml2 (Packagist) ECOSYSTEM:introduced=0,fixed=4.17.0; simplesamlphp/saml2-legacy (Packagist) ECOSYSTEM:introduced=0,fixed=4.17.0.
Is there a fix for CVE-2025-27773?
Yes. simplesamlphp/saml2 (Packagist): upgrade to 4.17.0 or later; simplesamlphp/saml2-legacy (Packagist): upgrade to 4.17.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2025-27773?
Check whether you run simplesamlphp/saml2 (Packagist) or simplesamlphp/saml2-legacy (Packagist) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • simplesamlphp/saml2 (Packagist): upgrade to 4.17.0 or later
    composer require simplesamlphp/saml2:^4.17.0
  • simplesamlphp/saml2-legacy (Packagist): upgrade to 4.17.0 or later
    composer require simplesamlphp/saml2-legacy:^4.17.0

Affected products

  • simplesamlphp/saml2 (Packagist) ECOSYSTEM:introduced=0,fixed=4.17.0
  • simplesamlphp/saml2-legacy (Packagist) ECOSYSTEM:introduced=0,fixed=4.17.0

Identifiers

  • CVE-2025-27773
  • GHSA-46r4-f8gj-xg56

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