Buffer Overflow Affecting zeromq3 package, versions *


Severity

Recommended
medium

Based on Red Hat Enterprise Linux security rating.

Threat Intelligence

EPSS
43.86% (99th percentile)

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  • Snyk IDSNYK-RHEL10-ZEROMQ3-9889430
  • published28 Apr 2025
  • disclosed1 Jan 2021

Introduced: 1 Jan 2021

CVE-2021-20235  (opens in a new tab)
CWE-120  (opens in a new tab)

How to fix?

There is no fixed version for RHEL:10 zeromq3.

NVD Description

Note: Versions mentioned in the description apply only to the upstream zeromq3 package and not the zeromq3 package as distributed by RHEL. See How to fix? for RHEL:10 relevant fixed versions and status.

There's a flaw in the zeromq server in versions before 4.3.3 in src/decoder_allocators.hpp. The decoder static allocator could have its sized changed, but the buffer would remain the same as it is a static buffer. A remote, unauthenticated attacker who sends a crafted request to the zeromq server could trigger a buffer overflow WRITE of arbitrary data if CURVE/ZAP authentication is not enabled. The greatest impact of this flaw is to application availability, data integrity, and confidentiality.

CVSS Base Scores

version 3.1