CVE-2026-21874
NiceGUI has Redis connection leak via tab storage causes service degradation
- State
- Published
- Severity
- 5.3 Medium
- Published
- Jan 8, 2026
- Updated
- Jan 8, 2026
- Reserved
- Jan 5, 2026
Description
NiceGUI is a Python-based UI framework. From versions v2.10.0 to 3.4.1, an unauthenticated attacker can exhaust Redis connections by repeatedly opening and closing browser tabs on any NiceGUI application using Redis-backed storage. Connections are never released, leading to service degradation when Redis hits its connection limit. NiceGUI continues accepting new connections - errors are logged but the app stays up with broken storage functionality. This issue has been patched in version 3.5.0.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 5.3 Medium | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L | GitHub_M |
Weaknesses
- CWE-772 Missing Release of Resource after Effective Lifetime
Affected Products
| Product | Versions |
|---|---|
niceguizauberzeug |
|
References
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