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CVE-2021-33503

Published: Jun 29, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSA BDUCWE-400
NVD MITRE
7.5CVSSHIGH
EPSS Score
3.3%
Top 13.2%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

An issue was discovered in urllib3 before 1.26.5. When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
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

urllib3pythonOSS Libraries
fedorafedoraproject
On-premOS
Operating Systems / linux-distro
enterprise manager ops centeroracle
On-premWeb App
Databases / db-tooling
instantis enterprisetrackoracle
On-premWeb App
Enterprise Software / itsm-monitoring
zfs storage appliance kitoracle
On-premDatabase
Databases / data-warehouse-analytics
pythonoss-projectUSOSS Libraries
fedoraprojectoss-projectUSOperating Systemsaka fedora project
oraclecommercialUSDatabasesaka oracle corp.
and 9 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

Official Patch Available

MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

https://github.com/advisories/GHSA-q2q7-5pp4-w6pg
github.com
https://github.com/urllib3/urllib3/commit/2d4a3fee6de2fa45eb82169361918f759269b4ec
github.com
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6SCV7ZNAHS3E6PBFLJGENCDRDRWRZZ6W/
lists.fedoraproject.org
and 21 more references View all →

Timeline

Published
Jun 29, 2021
Last Updated
Nov 21, 2024

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