CVE-2020-6817 - Vulnerability Details - OpenCVE

Description

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']}).

Published: 2023-02-16

Score: 7.5 High

EPSS: < 1% Very Low

KEV: No

Impact:

Action:

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Mozilla

Mozilla Bleach

affected

Version	Status	Constraints
`unspecified`	affected	< 3.1.4

Configuration 1 [-]

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

No data.

No data available yet.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

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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
Ubuntu USN	USN-8077-1	Bleach vulnerabilities

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 0.00581.

Exploitation poc

Automatable yes

Technical Impact partial

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'}`

Subscriptions

Mozilla Bleach

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.

Weaknesses

CWE-1333

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