phpseclib is a PHP secure communications library. Projects using versions 1.0.26 and below, 2.0.0 through 2.0.51, and 3.0.0 through 3.0.49 are vulnerable to a to padding oracle timing attack when using AES in CBC mode. This issue has been fixed in versions 1.0.27, 2.0.52 and 3.0.50.
https://github.com/phpseclib/phpseclib/security/advisories/GHSA-94g3-g5v7-q4jg
https://github.com/phpseclib/phpseclib/commit/ccc21aef71eb170e9bf819b167e67d1fd9e6e788
Published: 2026-03-20
Updated: 2026-03-20
Base Score: 4.3
Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:N/A:N
Severity: Medium
Base Score: 5.9
Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Severity: Medium
Base Score: 8.2
Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
Severity: High
EPSS: 0.00013