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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...

Published: Mar 7, 2022Updated: Nov 3, 2025 Sources: CVE List NVD BDU csafCWE-400
NVD MITRE
6.5CVSSMEDIUM
EPSS Score
4.7%
Top 9.4%
CISA KEV
Not in KEV
Exploits
1 Known
Remediation
Patch Available

Description

Multiple vulnerabilities have been identified in the additional GNU/Linux subsystem of the firmware version >= V3.1.0 and < V3.1.5 for the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP (incl. SIPLUS variant). These GNU/Linux vulnerabilities have been externally identified. Siemens has released new versions for the affected products and recommends to update to the latest versions. Note: This SSA advises vulnerabilities for firmware version V3.1 only; for versions < V3.1 refer to Siemens Security Bulletin SSB-439005 ( https://cert-portal.siemens.com/productcert/html/ssb-439005.html).

CVSS Vector Breakdown

AV:NAC:LPR:LUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-400

Affected Products

Astra Linux Special EditionООО «РусБИТех-Астра»
On-premOS
Operating Systems / linux-distro
Debian GNU/LinuxСообщество свободного программного обеспечения
On-premOS
Operating Systems / linux-distro
PythonPython Software FoundationOSS Libraries
РОСА ХРОМАО «НТЦ ИТ РОСА»
On-prem
Operating Systems / linux-distro
ОСОН ОСнова ОnyxАО «НППКТ»
On-premOS
Operating Systems / linux-distro
ооо «русбитех-астра»commercialRUOperating Systemsaka rusbitech-astra
сообщество свободного программного обеспеченияoss-projectOperating Systemsaka сообщество свободного программного обеспечения, fsf
python software foundationoss-projectUSOSS Librariesaka python software foundation, psf
ао «нтц ит роса»commercialRUOperating Systems
ао «нппкт»commercialRUOperating Systems
and 21 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

https://bugs.python.org/issue43075&#13;
bugs.python.org
https://github.com/python/cpython/commit/3fbe96123aeb66664fa547a8f6022efa2dc8788f&#13;
github.com
https://github.com/python/cpython/commit/7215d1ae25525c92b026166f9d5cac85fb1defe1&#13;
github.com
and 34 more references View all →

Timeline

Published
Mar 7, 2022
Last Updated
Nov 3, 2025

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