CVE-2026-17545PHP on Windows: Reserved Device Names Are Not Rejected Before File/Stream I/O which can cause DoS
Updated under an hour ago ()
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It affects PHP Group PHP and 1 other product. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
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Free account, 1 product
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.
- CVSS
- 6.9 MEDIUM (v4.0, CNA)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
- Weakness (CWE)
- CWE-67
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- php
- NVD analysis
- Analyzed
- Record last updated
- Sep 25, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
PHP Group PHP php_group:php (from the name) | from 8.2.* before 8.2.34; from 8.3.* before 8.3.35; from 8.4.* before 8.4.26; from 8.5.* before 8.5.11 | CNA record |
php php php:php | from 8.2.0 before 8.2.34; from 8.3.0 before 8.3.35; from 8.4.0 before 8.4.26; from 8.5.0 before 8.5.11 | NVD |
References
- https://github.com/php/php-src/security/advisories/GHSA-9f67-6fw4-hpfpvendor-advisory, exploit
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.