CVE-2020-6817

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']}).

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=1623633	Exploit Issue Tracking
https://github.com/mozilla/bleach/security/advisories/GHSA-vqhp-cxgc-6wmm	Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1623633	Exploit Issue Tracking
https://github.com/mozilla/bleach/security/advisories/GHSA-vqhp-cxgc-6wmm	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2023-02-16 22:15

Updated : 2025-03-19 16:15

NVD link : CVE-2020-6817

Mitre link : CVE-2020-6817

CVE.ORG link : CVE-2020-6817

JSON object : View

Products Affected

mozilla

bleach

CWE

CWE-1333

Inefficient Regular Expression Complexity

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