CVE-2021-3733
There's a flaw in urllib's AbstractBasicAuthHandler class. An attacker who controls a malicious HTTP server that an HTTP client (such as web browser) connects to, could trigger a Regular Expression Denial of Service (ReDOS) during an authentication request with a specially crafted payload that is sent by the server to the client. The greatest threat that this flaw poses is to application availability.
- Score
- CVSS 3.1 6.5 Medium
- Status
- Modified - secalert@redhat.com
- Published
- 2022-03-10
- Last modified
- 2026-10-14
- Weaknesses
- CWE-400
Affected products
- Extra Packages For Enterprise Linux (Fedoraproject)
- Fedora (Fedoraproject)
- Hci Compute Node Firmware (Netapp)
- Management Services For Element Software And Netapp Hci (Netapp)
- Ontap Select Deploy Administration Utility (Netapp)
- Solidfire, Enterprise Sds & Hci Storage Node (Netapp)
- Python (Python)
- Codeready Linux Builder (Redhat)
- Codeready Linux Builder For Ibm Z Systems (Redhat)
- Codeready Linux Builder For Power Little Endian (Redhat)
- Enterprise Linux (Redhat)
- Enterprise Linux Eus (Redhat)
- Enterprise Linux For Ibm Z Systems (Redhat)
- Enterprise Linux For Ibm Z Systems Eus (Redhat)
- Enterprise Linux For Power Little Endian (Redhat)
- Enterprise Linux For Power Little Endian Eus (Redhat)
- Enterprise Linux Server Aus (Redhat)
- Enterprise Linux Server For Power Little Endian Update Services For Sap Solutions (Redhat)
- Enterprise Linux Server Tus (Redhat)
- Enterprise Linux Server Update Services For Sap Solutions (Redhat)
- Simatic S7-1500 Cpu 1518-4 Pndp Mfp (Siemens)
- Simatic S7-1500 Cpu 1518f-4 Pndp Mfp (Siemens)
- Siplus S7-1500 Cpu 1518-4 Pndp Mfp (Siemens)
References
- https://bugs.python.org/issue43075
- https://bugzilla.redhat.com/show_bug.cgi?id=1995234
- https://github.com/python/cpython/pull/24391
- https://ubuntu.com/security/CVE-2021-3733
- https://github.com/python/cpython/commit/7215d1ae25525c92b026166f9d5cac85fb
- https://security.netapp.com/advisory/ntap-20220407-0001/
- https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html
- https://lists.debian.org/debian-lts-announce/2023/06/msg00039.html
- https://lists.debian.org/debian-lts-announce/2024/12/msg00000.html
- https://cert-portal.siemens.com/productcert/html/ssa-398330.html
