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CVE-2021-20236

Published: May 28, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-120
9.8CRITICAL
NVD MITRE
EPSS Score
1.6%
Top 26.5%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
Not available

Description

A flaw was found in the ZeroMQ server in versions before 4.3.3. This flaw allows a malicious client to cause a stack buffer overflow on the server by sending crafted topic subscription requests and then unsubscribing. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-120CWE-787

Affected Products

redhat
commercial·USaka red hat
ceph storageOn-prem
Operating Systems / linux-distro
enterprise linuxOn-premOS
Operating Systems / linux-distro
zeromq
oss-projectaka libzmq, 0mq, zmq
zeromqLibrary
OSS Libraries / generic-library
fedoraproject
oss-project·USaka fedora project
fedoraOn-premOS
Operating Systems / linux-distro
Сообщество свободного программного обеспечения
oss-projectaka fsf
ZeroMQOn-premLibrary
OSS Libraries / generic-library
ООО «Ред Софт»
commercial·RUaka red soft
РЕД ОСOn-premOS
Operating Systems / linux-distro
ООО «РусБИТех-Астра»
commercial·RUaka rusbitech-astra
Astra Linux Special EditionOn-premOS
Operating Systems / linux-distro
and 1 more affected products View all →

Exploitability

Official Patch Available
Is your org exposed to CVE-2021-20236?We can run the check for you — a free external exposure review, no install. Check my exposure

Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://bugzilla.redhat.com/show_bug.cgi?id=1921976
bugzilla.redhat.com
https://github.com/zeromq/libzmq/security/advisories/GHSA-qq65-x72m-9wr8
github.com
https://github.com/zeromq/libzmq/security/advisories/GHSA-qq65-x72m-9wr8
github.com
and 3 more references View all →

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