GHSA-5cjr-mxj5-wmrx
SimpleSAMLphp has Possible DoS via XPath Transform
Packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| Packagist | simplesamlphp/saml2 | >= 4.20.0, < 4.20.3 | 4.20.3 |
| Packagist | simplesamlphp/saml2-legacy | >= 4.20.0, < 4.20.3 | 4.20.3 |
| Packagist | simplesamlphp/saml2 | < 4.19.3 | 4.19.3 |
| Packagist | simplesamlphp/saml2-legacy | < 4.19.3 | 4.19.3 |
Details
As written in the advisory (Markdown source, shown as plain text).
## 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.
References
External links from the advisory. They lead to third-party sites.