Cyber Resilience

CVE-2025-66645

Path Traversal in Zauberzeug Nicegui ≤ 3.4.0

Public PoCPath Traversal
Published
09 December 2025
Modified
19 December 2025
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.011 63th percentile
Risk Priority 60 floored blend · peak EPSS

Summary

CVE-2025-66645 is a high-severity Path Traversal (CWE-22) vulnerability in Zauberzeug Nicegui. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 37% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

NiceGUI is a Python-based UI framework that is affected by a directory traversal vulnerability in versions 3.3.1 and below. The flaw resides in the App.add_media_files() function and is tracked as CWE-22, enabling unauthorized access to files outside intended directories. It carries a CVSS 3.1 score of 7.5 reflecting network attack vector, low complexity, and high confidentiality impact without any required authentication or user interaction. The issue was resolved in version 3.4.0.

A remote attacker can exploit the vulnerability over the network to read arbitrary files from the server filesystem, potentially exposing configuration data, source code, or other sensitive information stored on the host.

The official GitHub security advisory GHSA-hxp3-63hc-5366 and the associated commit a1b89e2a24e1911a40389ace2153a37f4eea92a9 confirm the patch in 3.4.0 and recommend upgrading as the primary mitigation. The EPSS score remains low with only a minor peak of 0.0111, indicating limited observed exploitation interest to date.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

NiceGUI is a Python-based UI framework. Versions 3.3.1 and below are vulnerable to directory traversal through the App.add_media_files() function, which allows a remote attacker to read arbitrary files on the server filesystem. This issue is fixed in version 3.4.0.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-25732Same product: Zauberzeug Nicegui
CVE-2026-39844Same product: Zauberzeug Nicegui
CVE-2025-21048Shared CWE-22
CVE-2026-23939Shared CWE-22
CVE-2024-7145Shared CWE-22
CVE-2023-42225Shared CWE-22
CVE-2024-33109Shared CWE-22
CVE-2023-35016Shared CWE-22
CVE-2025-10723Shared CWE-22
CVE-2023-1163Shared CWE-22

Affected Assets

zauberzeug
nicegui
≤ 3.4.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V5.3.2

Mitigating Controls (NIST 800-53 r5) AI

Enforces the intended directory access authorizations that path traversal would otherwise bypass.

Input validation directly neutralizes special path elements before pathname construction occurs.

Least privilege reduces the impact of any unauthorized file access obtained via traversal.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-02 partial match
prevents

Patching/maintenance can remediate known path-traversal flaws in deployed software (partial prevention of exploitability) but does nothing to stop the coding defect from being introduced in the first place.

PR.AA-05 none match
prevents

PR.AA-05 defines and reviews access policies but does not address code-level pathname neutralization, so neither direction prevents CWE-22.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing in development catches path traversal via static/dynamic analysis.

prevents

Secure SDLC mandates input validation and path sanitization that directly prevent path traversal.

prevents

Application security requirements include rules for safe file handling and canonicalization.

prevents

Secure architecture principles require least-privilege file access and directory isolation.

prevents

Secure coding standards explicitly forbid unsafe path construction and mandate safe APIs.

mitigates

Information access restriction limits which files an application may read or write.

References