Out-of-bounds write in PHP - CVE-2026-17544
Published: August 3, 2026
Vulnerability identifier: #VU140834
CSH Severity: Medium
CVSS v4: 9.2 [CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-17544
CWE-ID: CWE-787
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to compromise vulnerable system.
The vulnerability exists due to a boundary error when processing untrusted input within the bc_str2num() function. A remote attacker can pass specially crafted input to the application that is using the affected function, trigger an out-of-bounds write and crash the application or potentially execute arbitrary code.
Affected software
PHP
How to mitigate CVE-2026-17544
Install updates from vendor's website.
PHP - addressed in versions 8.4.24, 8.5.9