CVE-2021-20237
HIGH
7.5
CVSS Score
Published: May 28, 2021 at 10:42 AM UTC
Updated: June 17, 2026 at 03:33 AM UTC
2 products affected across 1 vendorLibzmqZeromq
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Severity
HIGH7.5
Exploit prediction
EPSS 2%
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.
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
References (2)
x_refsource_MISCIssue TrackingThird Party Advisory
Source: [email protected]
https://bugzilla.redhat.com/show_bug.cgi?id=1921989x_refsource_MISCPatchThird Party Advisory
Source: [email protected]
https://github.com/zeromq/libzmq/security/advisories/GHSA-4p5v-h92w-6wxwCVSS
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- NONE
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality
- NONE
- Integrity
- NONE
- Availability
- HIGH
Vector?
Quick Info
StatusMODIFIED
CWE
CWE-400CWE-401
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