Disclosure summary
Python 2.7 through 2.7.17, 3.5 through 3.5.9, 3.6 through 3.6.10, 3.7 through 3.7.6, and 3.8 through 3.8.1 allows an HTTP server to conduct Regular Expression Denial of Service (ReDoS) attacks against a client because of urllib.request.AbstractBasicAuthHandler catastrophic backtracking.
Source-reported weakness categories
CWE-400
Source-specific records & product guidance
Sources retain their own attribution and scoring. Follow the original record to confirm affected versions, fixed releases, and configuration conditions.
NIST National Vulnerability Database · NVD-CVE-2020-8492
Open original source · Updated Oct 07, 2026
Only CPE matches marked vulnerable=true are indexed. AND/OR platform conditions must be checked in the original NVD record.
| Vendor | Product / association | Version / bounds |
|---|---|---|
| python | python | * {"versionStartIncluding":"3.8.0","versionEndIncluding":"3.8.1"} |
| opensuse | leap | 15.1 |
| canonical | ubuntu_linux | 12.04 |
| canonical | ubuntu_linux | 14.04 |
| canonical | ubuntu_linux | 16.04 |
| canonical | ubuntu_linux | 18.04 |
| canonical | ubuntu_linux | 19.10 |
| canonical | ubuntu_linux | 20.04 |
| fedoraproject | fedora | 31 |
| fedoraproject | fedora | 32 |
| debian | debian_linux | 9.0 |
Original records & references
- NIST NVD record
- CVE Program record
- bugs.python.org — Issue Tracking, Vendor Advisory
- github.com — Patch, Third Party Advisory
- lists.apache.org
- lists.apache.org
- lists.debian.org — Mailing List, Third Party Advisory
- lists.debian.org
- lists.fedoraproject.org
- lists.fedoraproject.org
- lists.fedoraproject.org
- lists.fedoraproject.org
- python-security.readthedocs.io — Exploit, Third Party Advisory
- security.gentoo.org — Third Party Advisory
- security.netapp.com — Third Party Advisory
- usn.ubuntu.com — Third Party Advisory
- usn.ubuntu.com — Third Party Advisory
- bugs.python.org — Issue Tracking, Vendor Advisory
- github.com — Patch, Third Party Advisory
- lists.apache.org
- lists.apache.org
- lists.debian.org — Mailing List, Third Party Advisory
- lists.debian.org
- lists.fedoraproject.org
- lists.fedoraproject.org
- lists.fedoraproject.org
- lists.fedoraproject.org
- python-security.readthedocs.io — Exploit, Third Party Advisory
- security.gentoo.org — Third Party Advisory
- security.netapp.com — Third Party Advisory
- usn.ubuntu.com — Third Party Advisory
- usn.ubuntu.com — Third Party Advisory
PUBLISHED 2020-01-30T14:15:12-05:00
MODIFIED 2026-10-07T15:17:18-04:00
INGESTED 2026-10-08T12:30:34-04:00