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CVE-2020-6817 (GCVE-0-2020-6817)

Vulnerability from cvelistv5 – Published: 2023-02-16 00:00 – Updated: 2025-03-19 15:21
VLAI
Summary
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']}).
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-03-19 15:21 UTC
CWE
  • regular expression denial-of-service (ReDoS) in BleachSanitizerFilter.sanitize_css gauntlet regular expression
  • CWE-1333 - Inefficient Regular Expression Complexity
Assigner
References
Impacted products
Vendor Product Version CPE status
Mozilla Mozilla Bleach Affected: unspecified , < 3.1.4 (custom)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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