CVE-2021-23980
Public exploit available. Not confirmed exploited in the wild yet. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
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.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
1 source with a proof of concept or module.
Exploit links, PoCs and Metasploit modules after sign-in- EPSS
0.5% chance of exploitation activity in the next 30 days, which ranks it in the 39th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
The patch came 352 days before any public exploit.
- OpenVAS check added
- Public exploit / PoCsource: other
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Scored 6.1 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction RequiredA user must click a link, open a file, or perform some action
Scope
- Scope ChangedThe exploit can affect other components (e.g. sandbox escape, host compromise from VM)
Impact if exploited
- Confidentiality LowSome restricted information is disclosed, but limited in scope
- Integrity LowData modification is possible but limited in scope or consequence
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
References in the record
- github.com/mozilla/bleach/security/advisories/GHSA-vv2x-vrpj-qqpq
- bugzilla.mozilla.org/show_bug.cgi?id=CVE-2021-23980
- debian.org/security/2021/dsa-4892&
And 14 more references. See all after sign-in
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