What’s Vulnerable › Vulnerabilities
CVE-2026-7259: Null pointer dereference in php_mb_check_encoding() via mb_ereg_search_init()
- Severity: medium (CVSS 6.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.2% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-05-10 · updated 2026-07-24
- Weakness: CWE-476
Description
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: from 8.2.0 before 8.2.31; from 8.3.0 before 8.3.31; from 8.4.0 before 8.4.21; from 8.5.0 before 8.5.6 — fixed in 8.2.31, 8.3.31, 8.4.21, 8.5.6
How to fix
Upgrade to a fixed version: PHP 8.2.31, 8.3.31, 8.4.21, 8.5.6. Check the vendor advisory for mitigations.
References
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