CVE-2026-21873
Last modified
CVE-2026-21873 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. NiceGUI is a Python-based UI framework. From versions 2.22.0 to 3.4.1, an unsafe implementation in the pushstate event listener used by ui.sub_pages allows an attacker to manipulate the fragment identifier of the URL, which they can do despite being cross-site, using an iframe. EPSS estimates a 0.23% chance of exploitation in the next 30 days.
Description
NiceGUI is a Python-based UI framework. From versions 2.22.0 to 3.4.1, an unsafe implementation in the pushstate event listener used by ui.sub_pages allows an attacker to manipulate the fragment identifier of the URL, which they can do despite being cross-site, using an iframe. This issue has been patched in version 3.5.0.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Zauberzeug | Nicegui | >= 2.22.0, < 3.5.0 |
References
- https://github.com/zauberzeug/nicegui/security/advisories/GHSA-mhpg-c27v-6mxrExploit, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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