CVE-2021-20237

HIGH

libzmq 4.2.0-4.3.2 - Unauthenticated Memory Leak via Crafted PUB Messages

Title source: llm
STIX 2.1

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.

References (2)

Core 2
Core References
Issue Tracking, Third Party Advisory x_refsource_misc
https://bugzilla.redhat.com/show_bug.cgi?id=1921989

Scores

CVSS v3 7.5
EPSS 0.0169
EPSS Percentile 74.1%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Details

CWE
CWE-400 CWE-401
Status published
Products (1)
zeromq/libzmq 4.2.0 - 4.3.3
Published May 28, 2021
Tracked Since Feb 18, 2026