Firebase PHP-JWT < 6.0.0 - Algorithm Confusion

Access of Resource Using Incompatible Type ('Type Confusion')

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

CVE	CVE-2021-46743
CVSS	Critical (9.1)
Publicly Published	November 11, 2022
Last Updated	January 22, 2024

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. This may or may not be exploitable in WordPress plugins and themes using the library.

References

www.wordfence.com

1 affected software package

Software Type	Plugin
Software Slug	jwt-auth (view on wordpress.org)
Patched?	Yes
Affected Version	<= 2.1.0
Patched Version	2.1.1

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