Path Traversal in Zauberzeug Nicegui

CVE-2026-25732

NiceGUI is a Python-based UI framework. Prior to 3.7.0, NiceGUI's FileUpload.name property exposes client-supplied filename metadata without sanitization, enabling path traversal when developers use the pattern UPLOAD_DIR / file.name. Malicious filenames containing ../ sequences allow attackers to write files outside intended directories, with potential for remote code execution through application file overwrites in vulnerable deployment patterns. This design creates a prevalent security footgun affecting applications following common community patterns. Note: Exploitation requires application code incorporating file.name into filesystem paths without sanitization. Applications using fixed paths, generated filenames, or explicit sanitization are not affected. This vulnerability is fixed in 3.7.0.

Vulnerability class: Path Traversal (Directory Traversal)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.030 (86.9th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 87th percentile — 86.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-25732: held from 0.032 to 0.030.

EPSS over last 30 days · oldest: 0.032 · newest: 0.030 · change: -0.002

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2026-25732?
CVE-2026-25732 is a high-severity vulnerability in Zauberzeug Nicegui, classified under Path Traversal. CVSS score: 7.5/10. Published 2026-02-06.
How severe is CVE-2026-25732?
High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2026-25732 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.