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.
Metrics
Affected Vendors & Products
References
History
Mon, 03 Nov 2025 22:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Status: PUBLISHED
Assigner: redhat
Published: 2022-03-07T00:00:00.000Z
Updated: 2025-11-03T21:45:06.299Z
Reserved: 2021-08-23T00:00:00.000Z
Link: CVE-2021-3733
No data.
Status : Modified
Published: 2022-03-10T17:42:59.623
Modified: 2025-11-03T22:15:50.833
Link: CVE-2021-3733