vulnerability
Ubuntu: USN-8077-1 (CVE-2020-6817): Bleach vulnerabilities
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 8 | (AV:N/AC:L/Au:N/C:N/I:N/A:C) | Feb 16, 2023 | Jun 26, 2025 | Mar 27, 2026 |
Severity
8
CVSS
(AV:N/AC:L/Au:N/C:N/I:N/A:C)
Published
Feb 16, 2023
Added
Jun 26, 2025
Modified
Mar 27, 2026
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']}).
Solutions
ubuntu-pro-upgrade-python-bleachubuntu-pro-upgrade-python-bleach-docubuntu-pro-upgrade-python3-bleach
References
- CVE-2020-6817
- https://attackerkb.com/topics/CVE-2020-6817
- CWE-1333
- EUVD-EUVD-2020-0056
- UBUNTU-USN-8077-1
- https://bugzilla.mozilla.org/show_bug.cgi?id=1623633
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2020-0056
- https://github.com/mozilla/bleach/commit/6e74a5027b57055cdaeb040343d32934121392a7
- https://github.com/mozilla/bleach/commit/d6018f2539d271963c3e7f54f36ef11900363c69
- https://github.com/mozilla/bleach/security/advisories/GHSA-vqhp-cxgc-6wmm
- https://www.cve.org/CVERecord?id=CVE-2020-6817
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