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GHSA-8xf4-w7qw-pjjwcritical9.1

Firebase PHP-JWT key/algorithm type confusion

Impact

In Firebase PHP-JWT before 6.0.0, an algorithm-confusion issue (e.g., RS256 / HS256) exists via the kid (aka Key ID) header, when multiple types of keys are loaded in a key ring. This allows an attacker to forge tokens that validate under the incorrect key. NOTE: this provides a straightforward way to use the PHP-JWT library unsafely, but might not be considered a vulnerability in the library itself.

Source excerpt · OSV

Affected packages

Start with the recorded fix for your release branch. Check your installed version and test compatibility before upgrading. Fixing this advisory does not rule out other vulnerabilities in the release.

firebase/php-jwt Packagist
Affected rangeRecorded fix
Earlier releases before 6.0.0Ecosystem versions6.0.0

Version evidence: OSV · GHSA-8xf4-w7qw-pjjw

View original version evidence (14 explicit versions)

Original source description

In Firebase PHP-JWT before 6.0.0, an algorithm-confusion issue (e.g., RS256 / HS256) exists via the kid (aka Key ID) header, when multiple types of keys are loaded in a key ring. This allows an attacker to forge tokens that validate under the incorrect key. NOTE: this provides a straightforward way to use the PHP-JWT library unsafely, but might not be considered a vulnerability in the library itself.

References