CVE-2020-6817 - Vulnerability Details - OpenCVE

bleach.clean behavior parsing style attributes could result in a regular expression denial of service (ReDoS). Calls to bleach.clean with an allowed tag with an allowed style attribute are vulnerable to ReDoS. For example, bleach.clean(..., attributes={'a': ['style']}).

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00167.

Exploitation poc

Automatable yes

Technical Impact partial

Vendors	Products
Mozilla	Bleach

Configuration 1 [-]

cpe:2.3:a:mozilla:bleach:*:*:*:*:*:*:*:*

No data.

No data.

Advisories

Source	ID	Title
Debian DLA	DLA-2167-1	python-bleach security update
EUVD	EUVD-2020-0056	regular expression denial-of-service (ReDoS) in Bleach
Github GHSA	GHSA-vqhp-cxgc-6wmm	regular expression denial-of-service (ReDoS) in Bleach

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://bugzilla.mozilla.org/show_bug.cgi?id=1623633
https://github.com/mozilla/bleach/security/advisories/GHSA-vqhp-cxgc-6wmm

History

Wed, 19 Mar 2025 16:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

MITRE

Status: PUBLISHED

Assigner: mozilla

Published: 2023-02-16T00:00:00.000Z

Updated: 2025-03-19T15:21:23.888Z

Reserved: 2020-01-10T00:00:00.000Z

Link: CVE-2020-6817

Vulnrichment

Updated: 2024-08-04T09:11:05.144Z

NVD

Status : Modified

Published: 2023-02-16T22:15:10.650

Modified: 2025-03-19T16:15:14.917

Link: CVE-2020-6817

Redhat

No data.

OpenCVE Enrichment

No data.

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