CVE-2021-20237

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.

Categories

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 2.02% Top 20%
Third-Party Advisory redhat.com Third-Party Advisory github.com
Affected: n/a zeromq
Published at:
Updated at:

References

Link Tags
https://bugzilla.redhat.com/show_bug.cgi?id=1921989 issue tracking third party advisory
https://github.com/zeromq/libzmq/security/advisories/GHSA-4p5v-h92w-6wxw third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-20237?
CVE-2021-20237 has been scored as a high severity vulnerability.
How to fix CVE-2021-20237?
To fix CVE-2021-20237, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-20237 being actively exploited in the wild?
It is possible that CVE-2021-20237 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-20237?
CVE-2021-20237 affects n/a zeromq.
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