CVE-2026-7259: PHP

Medium severity, CVSS 6.5. EPSS: 0.3% chance of exploitation in the next 30 days.

In PHP versions 8.2.* before 8.2.31, 8.3.* before 8.3.31, 8.4.* before 8.4.21, and 8.5.* before 8.5.6, a mismatch between encoding lists in Oniguruma and mbfl leads to  a NULL pointer dereference, resulting in a segmentation fault and denial of service. The vulnerability is exploitable when user-controlled input can influence the encoding passed to mb_regex_encoding().

Affected products

• PHP PHP: from 8.2.0, before 8.2.31 (fixed in 8.2.31); from 8.3.0, before 8.3.31 (fixed in 8.3.31); from 8.4.0, before 8.4.21 (fixed in 8.4.21); from 8.5.0, before 8.5.6 (fixed in 8.5.6)

Published 2026-05-10. Last modified 2026-07-24.