CVE-2026-17545
PHP on Windows: Reserved Device Names Are Not Rejected Before File/Stream I/O which can cause DoS
- State
- Published
- Severity
- 6.9 Medium
- Published
- Sep 25, 2026
- Updated
- Sep 25, 2026
- Reserved
- Jul 27, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 6.9 Medium | 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 | php |
Weaknesses
- CWE-67 Improper handling of windows device names
Affected Products
| Product | Versions |
|---|---|
PHPPHP Group |
|
References
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