The verify function in Encryption/Symmetric.php in Malcolm Fell jwt before 1.0.3 does not use a timing-safe function for hash comparison, which allows attackers to spoof signatures via a timing attack.
https://github.com/emarref/jwt/releases/tag/1.0.3
https://github.com/emarref/jwt/pull/20
http://www.securityfocus.com/bid/95847
Source: Mitre, NVD
Published: 2017-01-23
Updated: 2026-06-17
Base Score: 5
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N
Severity: Medium
Base Score: 7.5
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Severity: High
EPSS: 0.0014