AUGUST 4, 2026
Live Feed
Back to database
Case File

CVE-2021-20236

CRITICAL · CVSS 9.8 EPSS 1.60% Public Exploit

Source: NVD + CISA KEV + EPSS (historical backfill) · Published 2021-05-28 · Last synced 2026-08-04

CyberRota Analysis

This is a critical severity vulnerability with a CVSS score of 9.8. Public exploit code or proof-of-concept references have been detected in its references.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

GitHub PoC Links

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2021-20236
Severity
CRITICAL
CVSS
9.8
EPSS
1.60%

Original NVD Description

A flaw was found in the ZeroMQ server in versions before 4.3.3. This flaw allows a malicious client to cause a stack buffer overflow on the server by sending crafted topic subscription requests and then unsubscribing. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

Related CVEs

Other vulnerabilities affecting the same vendor(s)