Medium severity · published May 10, 2026
CVE-2026-7259
Null pointer dereference in php_mb_check_encoding() via mb_ereg_search_init()
6.5
CVSS
0.2%
EPSS
No
On KEV
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().
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 8% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PH
PHP · PHP
8.2.* before 8.2.31; 8.3.* before 8.3.31; 8.4.* before 8.4.21; 8.5.* before 8.5.6 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-7259
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-7259
Vendor Advisory
https://github.com/php/php-src/security/advisories/GHSA-wm6j-2649-pv75
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