CVE-2026-102601
A path containing malformed UTF-8 causes PCRE to return false, so paths that also contain control characters bypass CorruptedPathDetected::forPath() in normalizePath().
Does this matter?
Lower severity and a low EPSS score (0.34%). Track it; it rarely justifies an emergency change on its own.
Description
Flysystem is an open source file storage library for PHP. Prior to 3.35.3, the default WhitespacePathNormalizer in src/WhitespacePathNormalizer.php used by Filesystem across adapters calls preg_match with the u modifier and treats both false and 0 as falsy. A path containing malformed UTF-8 causes PCRE to return false, so paths that also contain control characters bypass CorruptedPathDetected::forPath() in normalizePath(). Filesystem::write() can store such names and Filesystem::listContents() can return the raw ANSI escape sequences, allowing hidden or spoofed terminal file listings when an administrator displays them. This issue is fixed in version 3.35.3.
- CVSS 3.1
- 3.5 LOWCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
- EPSS
- 0.34% probability · 27th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-150
- Source
- security-advisories@github.com
EPSS moved from 0.3% on 30 September 2026 to 0.3% on 26 October 2026.
References
- https://github.com/thephpleague/flysystem/commit/ef4a9a557d769b5d472c403125716706a0d9cc77
- https://github.com/thephpleague/flysystem/releases/tag/3.35.3
- https://github.com/thephpleague/flysystem/security/advisories/GHSA-cxf4-7mrp-vvpr
- https://github.com/thephpleague/flysystem/security/advisories/GHSA-cxf4-7mrp-vvpr
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.