TI-2020-05526 Aliases CVE-2020-6816 GHSA-m6xf-fq7q-8743

Cross-site scripting in Mozilla Bleach

LOW 30CWE-79Published 2020-03-24 · Updated 2024-08-04

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 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-79.

Summary

In Mozilla Bleach before 3.12, a mutation XSS in bleach.clean when RCDATA and either svg or math tags are whitelisted and the keyword argument strip=False.

Why it matters now

EPSS 0.0134 71st percentileScored 2026-11-07

Public exploit Yes 2 exploit referencesTagged by NVD

Fix Fixed bleach (PyPI): 3.1.2

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
—	Mozilla Bleach	up to 3.11	—	No fix listed	CNA
—	bleach (PyPI)	before 3.1.2	3.1.2	Patch available	GHSA-m6xf-fq7q-8743

Mozilla Bleach Vendor— Affected up to 3.11 Fixed in — No fix listed CNA
bleach (PyPI) Vendor— Affected before 3.1.2 Fixed in 3.1.2 Patch available GHSA-m6xf-fq7q-8743

CPE configurations NVD · 2

CPE	Versions	Role	Vendor
cpe:2.3:a:mozilla:bleach::::::::	before 3.1.2	Vulnerable	Mozilla
cpe:2.3:o:fedoraproject:fedora:33:::::::*	33	Vulnerable	Fedoraproject

cpe:2.3:a:mozilla:bleach:*:*:*:*:*:*:*:* Versions before 3.1.2 Vulnerable ·Mozilla
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* Versions 33 Vulnerable ·Fedoraproject

Remediation

Fix · GHSA-m6xf-fq7q-8743 bleach (PyPI) Fixed in 3.1.2 Advisory →

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product

Red Hat

Timeline

2026-10-02 Threatist record created from CVE-2020-6816
2026-10-03 Alias added: GHSA-m6xf-fq7q-8743

References

Exploit 2

Advisory 3

Other 4

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences