CVE-2021-46743 Information

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.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Reference

https://github.com/firebase/php-jwt/issues/351

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

NONE

Base Severity

9.1