Improper Handling of Windows Device Names Affecting php/php-src package, versions [,8.2.34)[8.3.0RC1,8.3.35)[8.4.0RC1,8.4.26)[8.5.0RC1,8.5.11)
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-UNMANAGED-PHPPHPSRC-20158676
- published27 Sept 2026
- disclosed25 Sept 2026
- creditcrisprss,OSTIF-Derek
Introduced: 25 Sep 2026
NewCVE-2026-17545 (opens in a new tab)How to fix?
Upgrade php/php-src to version 8.2.34, 8.3.35, 8.4.26, 8.5.11 or higher.
Overview
Affected versions of this package are vulnerable to Improper Handling of Windows Device Names in php_stream_open_wrapper_ex(), php_win32_ioutil_open_w(), VCWD_RENAME(), and php_copy_file_ex(), which do not reject reserved names such as CON, PRN, AUX, NUL, COM1 through COM9, LPT1 through LPT9, CONIN$, and CONOUT$ when they appear as a path component, so the resulting handle refers to a device rather than a file. An attacker can hang a request and exhaust the worker pool by repeatedly supplying one of those names as a filename in an upload or download parameter, since I/O against a blocking device never returns, and reads and writes against the others do not behave as file operations. This affects only Windows deployments where the application builds paths from user input, and the path component matching is case insensitive and applies with or without an extension.