What’s Vulnerable › Vulnerabilities
CVE-2026-17544: Out-of-bounds write in bccomp() via crafted operand and scale
- Severity: critical (CVSS 9.8 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.4% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-07-30 · updated 2026-10-23
- Weakness: CWE-787
Description
Attacker-provided inputs to bccomp() could lead to an out-of-bounds write with stack and heap corruption in PHP versions from 8.4.* before 8.4.24 and from 8.5.* before 8.5.9.
Affected products
- PHP: from 8.4.0 before 8.4.24; from 8.5.0 before 8.5.9 — fixed in 8.4.24, 8.5.9
How to fix
Upgrade to a fixed version: PHP 8.4.24, 8.5.9. Check the vendor advisory for mitigations.
References
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