VULNERABILITY INTELLIGENCE

CVE-2026-39844

CVSS score5.9 MEDIUM
EPSS probability0.37%
CISA KEVNot currently listed
Published2026-04-08
Last modified2026-07-24
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Description

NiceGUI is a Python-based UI framework. Prior to 3.10.0, Since PurePosixPath only recognizes forward slashes (/) as path separators, an attacker can bypass this sanitization on Windows by using backslashes (\) in the upload filename. Applications that construct file paths using file.name (a pattern demonstrated in NiceGUI's bundled examples) are vulnerable to arbitrary file write on Windows. This vulnerability is fixed in 3.10.0.

Weakness classification

  • security-advisories@github.com: CWE-22

Primary references