CVE-2021-3733
3Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackepss 4.7%
exploitation probability
4.7%top 9% of all CVEs
observed exploitation
nono source reports it
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.
Affected products
n/a · pythonReferences
https://bugs.python.org/issue43075https://bugzilla.redhat.com/show_bug.cgi?id=1995234https://github.com/python/cpython/commit/7215d1ae25525c92b026166f9d5cac85fbhttps://github.com/python/cpython/pull/24391https://lists.debian.org/debian-lts-announce/2023/05/msg00024.htmlhttps://lists.debian.org/debian-lts-announce/2023/06/msg00039.htmlhttps://lists.debian.org/debian-lts-announce/2024/12/msg00000.htmlhttps://security.netapp.com/advisory/ntap-20220407-0001/https://ubuntu.com/security/CVE-2021-3733