## Summary This library turned out to be vulnerable to Denial-of-Service attacks using XPath transforms. A mitigation has been put in place to restrict the number of transforms and to restrict transforms to only the transform-algorithms mentioned in the SAML 2.0 Core Specifications (and specifically refuse XPath transforms). ## Impact An attacker is able to send specially crafted messages to any entity relying on SimpleSAMLphp (or directly on this SAML2-library) to be able to perform a Denial-of-Service attack.
Update simplesamlphp/saml2 to 4.20.3; simplesamlphp/saml2-legacy to 4.20.3 if you use the affected versions. Test the change in a non-production environment first.
Local check
hol-guard supply-chain scanSimpleSAMLphp has Possible DoS via XPath Transform affects simplesamlphp/saml2 (composer), simplesamlphp/saml2-legacy (composer). Severity is high. ## Summary This library turned out to be vulnerable to Denial-of-Service attacks using XPath transforms. A mitigation has been put in place to restrict the number of transforms and to restrict transforms to only the transform-algorithms mentioned in the SAML 2.0 Core Specifications (and specifically refuse XPath transforms). ## Impact An attacker is able to send specially crafted messages to any entity relying on SimpleSAMLphp (or directly on this SAML2-library) to be able to perform a Denial-of-Service attack.
AI coding agents often install or upgrade packages automatically in composer. A high vulnerability in a dependency can be pulled into a project through a normal install or update without a human reviewing the change, expanding the blast radius from a single package to every agent workspace that depends on it.
| Package | Affected range | Fixed version |
|---|---|---|
| simplesamlphp/saml2composer |
## Summary This library turned out to be vulnerable to Denial-of-Service attacks using XPath transforms. A mitigation has been put in place to restrict the number of transforms and to restrict transforms to only the transform-algorithms mentioned in the SAML 2.0 Core Specifications (and specifically refuse XPath transforms). ## Impact An attacker is able to send specially crafted messages to any entity relying on SimpleSAMLphp (or directly on this SAML2-library) to be able to perform a Denial-of-Service attack.
Update simplesamlphp/saml2 to 4.20.3; simplesamlphp/saml2-legacy to 4.20.3 if you use the affected versions. Test the change in a non-production environment first.
Local check
hol-guard supply-chain scanSimpleSAMLphp has Possible DoS via XPath Transform affects simplesamlphp/saml2 (composer), simplesamlphp/saml2-legacy (composer). Severity is high. ## Summary This library turned out to be vulnerable to Denial-of-Service attacks using XPath transforms. A mitigation has been put in place to restrict the number of transforms and to restrict transforms to only the transform-algorithms mentioned in the SAML 2.0 Core Specifications (and specifically refuse XPath transforms). ## Impact An attacker is able to send specially crafted messages to any entity relying on SimpleSAMLphp (or directly on this SAML2-library) to be able to perform a Denial-of-Service attack.
AI coding agents often install or upgrade packages automatically in composer. A high vulnerability in a dependency can be pulled into a project through a normal install or update without a human reviewing the change, expanding the blast radius from a single package to every agent workspace that depends on it.
| Package | Affected range | Fixed version |
|---|---|---|
| simplesamlphp/saml2composer |
| <=4.20.2 |
| 4.20.3 |
| simplesamlphp/saml2-legacycomposer | <=4.20.2 | 4.20.3 |
|---|
Fixed versions are reported by the source feed; confirm compatibility before updating.
Reported by GitHub Security Advisories (ghsa).
HOL Guard can help your team review package activity against supported protection paths.
Explore HOL Guard| <=4.20.2 |
| 4.20.3 |
| simplesamlphp/saml2-legacycomposer | <=4.20.2 | 4.20.3 |
|---|
Fixed versions are reported by the source feed; confirm compatibility before updating.
Reported by GitHub Security Advisories (ghsa).
HOL Guard can help your team review package activity against supported protection paths.
Explore HOL Guard