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CVE-2021-20237

Published: May 28, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-400
7.5HIGH
NVD MITRE
EPSS Score
1.7%
Top 25.1%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

An uncontrolled resource consumption (memory leak) flaw was found in ZeroMQ's src/xpub.cpp in versions before 4.3.3. This flaw allows a remote unauthenticated attacker to send crafted PUB messages that consume excessive memory if the CURVE/ZAP authentication is disabled on the server, causing a denial of service. The highest threat from this vulnerability is to system availability.

No summary for this CVE yet.

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-400CWE-401

Affected Products

Сообщество свободного программного обеспечения
oss-projectaka fsf
Debian GNU/LinuxOn-premOS
Operating Systems / linux-distro
ZeroMQOn-premLibrary
OSS Libraries / generic-library
ООО «РусБИТех-Астра»
commercial·RUaka rusbitech-astra
Astra Linux Special EditionOn-premOS
Operating Systems / linux-distro
zeromq
oss-projectaka 0mq, zmq, libzmq
libzmqLibrary
OSS Libraries / generic-library
and 1 more affected products View all →

Exploitability

Official Patch Available
Is your org exposed to CVE-2021-20237?We can run the check for you — a free external exposure review, no install. Check my exposure

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

https://bugzilla.redhat.com/show_bug.cgi?id=1921989
bugzilla.redhat.com
https://github.com/zeromq/libzmq/security/advisories/GHSA-4p5v-h92w-6wxw
github.com
https://nvd.nist.gov/vuln/detail/CVE-2021-20237
nvd.nist.gov
and 5 more references View all →

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