CVE-2026-21874

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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/zauberzeug/nicegui/commit/6c52eb2c90c4b67387c025b29646b4bc1578eb83	Patch
https://github.com/zauberzeug/nicegui/releases/tag/v3.5.0	Release Notes
https://github.com/zauberzeug/nicegui/security/advisories/GHSA-mp55-g7pj-rvm2	Exploit Vendor Advisory
https://github.com/zauberzeug/nicegui/security/advisories/GHSA-mp55-g7pj-rvm2	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:zauberzeug:nicegui:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-01-08 10:15

Updated : 2026-01-15 17:50

NVD link : CVE-2026-21874

Mitre link : CVE-2026-21874

CVE.ORG link : CVE-2026-21874

JSON object : View

Products Affected

zauberzeug

nicegui

CWE

CWE-772

Missing Release of Resource after Effective Lifetime

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