CVE-2021-3733
4 Medium
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
SINGLE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:S/C:N/I:N/A:P
6.5 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
0.003 Low
EPSS
Percentile
71.7%
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 configurations
References
bugs.python.org/issue43075
bugzilla.redhat.com/show_bug.cgi?id=1995234
github.com/python/cpython/commit/7215d1ae25525c92b026166f9d5cac85fb
github.com/python/cpython/pull/24391
lists.debian.org/debian-lts-announce/2023/05/msg00024.html
lists.debian.org/debian-lts-announce/2023/06/msg00039.html
security.netapp.com/advisory/ntap-20220407-0001/
ubuntu.com/security/CVE-2021-3733
Related
4 Medium
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
SINGLE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:S/C:N/I:N/A:P
6.5 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
0.003 Low
EPSS
Percentile
71.7%