CVE-2026-33332
HIGHNiceGUI's unvalidated chunk size parameter in media routes can cause memory exhaustion
Title source: cnaDescription
NiceGUI is a Python-based UI framework. Prior to version 3.9.0, NiceGUI's app.add_media_file() and app.add_media_files() media routes accept a user-controlled query parameter that influences how files are read during streaming. The parameter is passed to the range-response implementation without validation, allowing an attacker to bypass chunked streaming and force the server to load entire files into memory at once. With large media files and concurrent requests, this can lead to excessive memory consumption, degraded performance, or denial of service. This issue has been patched in version 3.9.0.
References (3)
Core 3
Core References
X_Refsource_Confirm x_refsource_confirm
https://github.com/zauberzeug/nicegui/security/advisories/GHSA-w5g8-5849-vj76
X_Refsource_Misc x_refsource_misc
https://github.com/zauberzeug/nicegui/commit/9026962b8c4f3f225c98b2fbc35aa6b60cb3495b
X_Refsource_Misc x_refsource_misc
https://github.com/zauberzeug/nicegui/releases/tag/v3.9.0
Scores
CVSS v3
7.5
EPSS
0.0060
EPSS Percentile
43.8%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-20
CWE-770
Status
published
Products (2)
pypi/nicegui
0 - 3.9.0PyPI
zauberzeug/nicegui
< 3.9.0 (2 CPE variants)
Published
Mar 24, 2026
Tracked Since
Mar 25, 2026