CVE-2021-20237

    Dashboard / Vulnerabilities / CVE-2021-20237

    CVE-2021-20237

    Published: 28 May 2021Last Modified: 9 Jul 2026

    Summary:

    Details: 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: https://bugzilla.redhat.com/show_bug.cgi?id=1921989, https://github.com/zeromq/libzmq/security/advisories/GHSA-4p5v-h92w-6wxw

    Affected packages

    Package

    Name:

    Purl:

    Affected ranges

    Type: GIT

    Events:

    Introduced- 097bf26e8dacf73abc2a6cdd6f9e4dce824b8208
    Fixed -04f5bbedee58c538934374dc45182d8fc5926fa3

    Affected versions

    v4.3.2
    v4.3.1
    v4.3.0

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    CVE-2021-20237 | CVE-DB