Cross-site scripting (XSS) vulnerability in the _keyify function in mistune.py in Mistune…
Priority LOW 32CWE-79Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- Fixed
Attack profile from CVSS 3.0 · NVD. Fix status from CNA and GitHub. Impact type from CWE-79.
Summary
Cross-site scripting (XSS) vulnerability in the _keyify function in mistune.py in Mistune before 0.8.1 allows remote attackers to inject arbitrary web script or HTML by leveraging failure to escape the "key" argument.
Why it matters now
EPSS 0.02235 82nd percentileScored 2026-11-07
Fix Fixed mistune (PyPI): 0.8.1
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
| — | mistune (PyPI) | before 0.8.1 | 0.8.1 | Patch available | GHSA-98gj-wwxm-cj3h |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
- mistune (PyPI) Vendor— Affected before 0.8.1 Fixed in 0.8.1 Patch available GHSA-98gj-wwxm-cj3h
CPE configurations NVD · 2
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mistune_project:mistune:*:*:*:*:*:*:*:* | before 0.8.1 | Vulnerable | lepture |
| cpe:2.3:o:fedoraproject:fedora:26:*:*:*:*:*:*:* | 26 | Vulnerable | Fedoraproject |
- cpe:2.3:a:mistune_project:mistune:*:*:*:*:*:*:*:* Versions before 0.8.1 Vulnerable ·lepture
- cpe:2.3:o:fedoraproject:fedora:26:*:*:*:*:*:*:* Versions 26 Vulnerable ·Fedoraproject
Remediation
- Fix · GHSA-98gj-wwxm-cj3h mistune (PyPI) Fixed in 0.8.1 Advisory →
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2017-16876
- 2026-10-03 Alias added: GHSA-98gj-wwxm-cj3h
References
Advisory 4
Sources
- CVE-2017-16876 · CVE Program
- CVE-2017-16876 · NVD
- FIRST EPSS
- GHSA-98gj-wwxm-cj3h · GitHub Advisory Database · CC BY 4.0
- CVE-2017-16876 · Red Hat security data · CC BY 4.0
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