id: PYSEC-2026-2234
published: "2026-04-08T21:16:59.883Z"
modified: "2026-07-13T05:50:15.036912Z"
aliases:
- CVE-2026-39844
- GHSA-w8wv-vfpc-hw2w
details: "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."
affected:
- package:
    name: nicegui
    ecosystem: PyPI
    purl: pkg:pypi/nicegui
  ranges:
  - type: ECOSYSTEM
    events:
    - introduced: "0"
    - fixed: 3.10.0
  versions:
  - 0.1.0
  - 0.1.4
  - 0.1.6
  - 0.2.0
  - 0.2.1
  - 0.2.10
  - 0.2.11
  - 0.2.12
  - 0.2.13
  - 0.2.14
  - 0.2.15
  - 0.2.2
  - 0.2.3
  - 0.2.4
  - 0.2.9
  - 0.3.0
  - 0.3.1
  - 0.3.2
  - 0.3.3
  - 0.3.4
  - 0.3.5
  - 0.3.6
  - 0.3.7
  - 0.3.8
  - 0.3.9
  - 0.4.0
  - 0.4.1
  - 0.4.10
  - 0.4.11
  - 0.4.12
  - 0.4.13
  - 0.4.14
  - 0.4.15
  - 0.4.2
  - 0.4.3
  - 0.4.4
  - 0.4.5
  - 0.4.6
  - 0.4.7
  - 0.4.8
  - 0.4.9
  - 0.5.0
  - 0.5.1
  - 0.5.10
  - 0.5.11
  - 0.5.12
  - 0.5.2
  - 0.5.3
  - 0.5.4
  - 0.5.5
  - 0.5.6
  - 0.5.7
  - 0.5.8
  - 0.5.9
  - 0.6.0
  - 0.6.1
  - 0.6.10
  - 0.6.11
  - 0.6.12
  - 0.6.13
  - 0.6.2
  - 0.6.3
  - 0.6.4
  - 0.6.5
  - 0.6.6
  - 0.6.7
  - 0.6.8
  - 0.6.9
  - 0.7.0
  - 0.7.1
  - 0.7.10
  - 0.7.11
  - 0.7.12
  - 0.7.13
  - 0.7.14
  - 0.7.15
  - 0.7.16
  - 0.7.17
  - 0.7.18
  - 0.7.19
  - 0.7.2
  - 0.7.21
  - 0.7.22
  - 0.7.23
  - 0.7.24
  - 0.7.25
  - 0.7.26
  - 0.7.27
  - 0.7.28
  - 0.7.29
  - 0.7.3
  - 0.7.30
  - 0.7.4
  - 0.7.6
  - 0.7.7
  - 0.7.8
  - 0.7.9
  - 0.8.0
  - 0.8.1
  - 0.8.10
  - 0.8.11
  - 0.8.12
  - 0.8.13
  - 0.8.14
  - 0.8.15
  - 0.8.16
  - 0.8.2
  - 0.8.3
  - 0.8.4
  - 0.8.5
  - 0.8.6
  - 0.8.7
  - 0.8.8
  - 0.8.9
  - 0.9.0
  - 0.9.1
  - 0.9.10
  - 0.9.11
  - 0.9.12
  - 0.9.13
  - 0.9.14
  - 0.9.15
  - 0.9.16
  - 0.9.17
  - 0.9.18
  - 0.9.19
  - 0.9.2
  - 0.9.20
  - 0.9.21
  - 0.9.22
  - 0.9.23
  - 0.9.24
  - 0.9.25
  - 0.9.26
  - 0.9.27
  - 0.9.28
  - 0.9.3
  - 0.9.4
  - 0.9.5
  - 0.9.6
  - 0.9.7
  - 0.9.8
  - 0.9.9
  - 1.0.1
  - 1.0.10
  - 1.0.2
  - 1.0.3
  - 1.0.4
  - 1.0.5
  - 1.0.6
  - 1.0.7
  - 1.0.8
  - 1.0.9
  - 1.1.0
  - 1.1.1
  - 1.1.10
  - 1.1.11
  - 1.1.2
  - 1.1.3
  - 1.1.4
  - 1.1.5
  - 1.1.6
  - 1.1.7
  - 1.1.8
  - 1.1.9
  - 1.2.0
  - 1.2.1
  - 1.2.10
  - 1.2.11
  - 1.2.12
  - 1.2.13
  - 1.2.14
  - 1.2.15
  - 1.2.16
  - 1.2.17
  - 1.2.18
  - 1.2.2
  - 1.2.20
  - 1.2.21
  - 1.2.22
  - 1.2.23
  - 1.2.24
  - 1.2.3
  - 1.2.4
  - 1.2.5
  - 1.2.6
  - 1.2.7
  - 1.2.8
  - 1.2.9
  - 1.3.0
  - 1.3.1
  - 1.3.10
  - 1.3.11
  - 1.3.12
  - 1.3.13
  - 1.3.14
  - 1.3.15
  - 1.3.16
  - 1.3.17
  - 1.3.18
  - 1.3.2
  - 1.3.3
  - 1.3.4
  - 1.3.5
  - 1.3.6
  - 1.3.7
  - 1.3.8
  - 1.3.9
  - 1.4.0
  - 1.4.1
  - 1.4.10
  - 1.4.11
  - 1.4.12
  - 1.4.13
  - 1.4.14
  - 1.4.15
  - 1.4.16
  - 1.4.17
  - 1.4.18
  - 1.4.19
  - 1.4.2
  - 1.4.20
  - 1.4.21
  - 1.4.22
  - 1.4.23
  - 1.4.24
  - 1.4.25
  - 1.4.26
  - 1.4.27
  - 1.4.28
  - 1.4.29
  - 1.4.3
  - 1.4.30
  - 1.4.31
  - 1.4.33
  - 1.4.34
  - 1.4.35
  - 1.4.36
  - 1.4.37
  - 1.4.4
  - 1.4.5
  - 1.4.6
  - 1.4.7
  - 1.4.8
  - 1.4.9
  - 2.0.0
  - 2.0.1
  - 2.1.0
  - 2.10.0
  - 2.10.1
  - 2.11.0
  - 2.11.1
  - 2.12.0
  - 2.12.1
  - 2.13.0
  - 2.14.0
  - 2.14.1
  - 2.15.0
  - 2.16.0
  - 2.16.1
  - 2.17.0
  - 2.18.0
  - 2.19.0
  - 2.2.0
  - 2.20.0
  - 2.21.0
  - 2.21.1
  - 2.22.0
  - 2.22.1
  - 2.22.2
  - 2.23.0
  - 2.23.1
  - 2.23.2
  - 2.23.3
  - 2.24.0
  - 2.24.1
  - 2.24.2
  - 2.3.0
  - 2.4.0
  - 2.5.0
  - 2.7.0
  - 2.8.0
  - 2.8.1
  - 2.9.0
  - 2.9.1
  - 3.0.0
  - 3.0.0rc1
  - 3.0.1
  - 3.0.2
  - 3.0.3
  - 3.0.4
  - 3.1.0
  - 3.2.0
  - 3.3.0
  - 3.3.1
  - 3.4.0
  - 3.4.1
  - 3.5.0
  - 3.6.0
  - 3.6.1
  - 3.7.0
  - 3.7.1
  - 3.8.0
  - 3.9.0
  ecosystem_specific: {}
references:
- type: ADVISORY
  url: https://github.com/zauberzeug/nicegui/releases/tag/v3.10.0
- type: ADVISORY
  url: https://github.com/zauberzeug/nicegui/security/advisories/GHSA-w8wv-vfpc-hw2w
- type: FIX
  url: https://github.com/zauberzeug/nicegui/commit/d38a702e3af2da5b0708f689be8d71413fc77056
severity:
- type: CVSS_V3
  score: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N