Arbitrary Code Injection Affecting mistune package, versions [,3.3.0)
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-PYTHON-MISTUNE-21460665
- published23 Oct 2026
- disclosed22 Oct 2026
- creditoffset
Introduced: 22 Oct 2026
NewCVE-2026-115351 (opens in a new tab)How to fix?
Upgrade mistune to version 3.3.0 or higher.
Overview
Affected versions of this package are vulnerable to Arbitrary Code Injection via the figwidth option in src/mistune/directives/image.py, where an attacker can supply an arbitrary string value for the figwidth directive option that is passed through without validation into the rendered HTML figure attributes, allowing injection of unsanitized content. This can lead to information disclosure through malicious attribute values rendered in the output document.