CVE-2026-7568: Signed integer overflow in metaphone()

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% 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-125

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, the metaphone() function in ext/standard/metaphone.c uses a signed int variable to track the current position within the input string. If a string longer than 2,147,483,647 bytes is passed, a signed integer overflow occurs, resulting in undefined behavior. This can lead to an out-of-bounds read, causing a segmentation fault or access to unrelated memory, and may affect the availability of the PHP process.

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

Get alerted when CVE-2026-7568 or the next vulnerability affects your stack