Description
Gitea's Jupyter notebook renderer inserts the notebook's language_info.name metadata into a CSS class attribute while disabling sanitization and rendering directly in the main document without an iframe sandbox. A malicious repository notebook can supply multiple CSS classes that create a viewport-covering overlay and intercept clicks when another user views it. The reported impact is UI redress; script execution was not demonstrated.
References5
Metrics
- CVSS 3.1
-
3.5
LOW
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N - EPSS — exploit probability
- 0% percentile: 31 · as of 11 November 2026
- CWE
- CWE-79CWE-1021
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