Medium severity · published Apr 1, 2021
CVE-2021-20234
An uncontrolled resource consumption (memory leak) flaw was found in the ZeroMQ client in versions before 4.3.3 in src/pipe.cpp
6.5
CVSS
1.1%
EPSS
No
On KEV
Description
An uncontrolled resource consumption (memory leak) flaw was found in the ZeroMQ client in versions before 4.3.3 in src/pipe.cpp. This issue causes a client that connects to multiple malicious or compromised servers to crash. The highest threat from this vulnerability is to system availability.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.1% · higher than 65% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Libzmq · Zeromq
before 4.3.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-20234
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-20234
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=1921972
Exploit
https://github.com/zeromq/libzmq/security/advisories/GHSA-wfr2-29gj-5w87
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