XSS in Mozilla Bleach
CVE-2021-23980
A mutation XSS affects users calling bleach.clean with all of: svg or math in the allowed tags p or br in allowed tags style, title, noscript, script, textarea, noframes, iframe, or xmp in allowed tags the keyword argument strip_comments=False Note: none of the above tags are in the default allowed tags and strip_comments defaults to True.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.005 (39.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 39th percentile — 39.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: +0.000
Affected products
- Mozilla Bleach
- Mozilla Bleach — versions unspecified
Weakness classification (CWE)
References
- github.com/mozilla/bleach/security/advisories/GHSA-vv2x-vrpj-qqpq (Vendor Advisory)
- bugzilla.mozilla.org/show_bug.cgi (Exploit, Issue Tracking)
Frequently asked questions
- What is CVE-2021-23980?
- CVE-2021-23980 is a medium-severity vulnerability in Mozilla Bleach, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2023-02-16.
- How severe is CVE-2021-23980?
- Medium severity. CVSS v3 base score is 6.1 out of 10.