CVE-2026-17545CWE-67

CVE-2026-17545

High · published September 26, 2026

CVSS v3.1
7.5
EPSS
0%
Percentile
24.0
In the wild
Unconfirmed
What it is

On Windows, PHP's filesystem and stream APIs do not reject reserved device names such as CON, PRN, AUX, NUL, COM1 to COM9, LPT1 to LPT9, CONIN$ and CONOUT$ when they appear as a component of a path. An attacker-controlled filename therefore reaches CreateFileW() and opens a device instead of the regular file the application expected, which can block or hang the request and exhaust worker processes.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
6.9 · CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:H
EPSS
0.00322 · 24.0th percentile
Weakness
CWE-67 · Improper Handling of Windows Device Names
Published
2026-09-26T01:17Z
Affected products (4)
ProductVersionsFixed in
php/php≥ 8.2.0, < 8.2.348.2.34
php/php≥ 8.3.0, < 8.3.358.3.35
php/php≥ 8.4.0, < 8.4.268.4.26
php/php≥ 8.5.0, < 8.5.118.5.11
References (2)
https://github.com/php/php-src/security/advisories/GHSA-9f67-6fw4-hpfp · [email protected]https://github.com/php/php-src/security/advisories/GHSA-9f67-6fw4-hpfp · 134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS history
Timeline
  • 27 SEP 03:25Z
    EPSS moved — → 0%
    epss
  • 25 SEP 20:18Z
    PHP on Windows: Reserved Device Names Are Not Rejected Before File/Stream I/O which can cause DoS
    cvelistv5