CVE-2021-20234

mediumpriority · track · 26EPSS 0.011 · 65 %ileEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
1.07% (65th) EPSS
CVSS 4.3 · medium
Is it mine?
12 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-28

An uncontrolled resource consumption (memory leak) flaw was found in the ZeroMQ client in versions before 4.3.3 in src/pipe.cpp. This issue causes a client that connects to multiple malicious or compromised servers to crash. The highest threat from this vulnerability is to system availability.

01

cvss

Technical severity, 0–10. One row per scoring source.

6.5
010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 8.6 · impact 2.9
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 3.6
v3.16.5mediumAV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU
v3.16mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
02

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-401USprimaryCWE-400USCWE-400US
03

affected products (12)

Products and version ranges known to be affected.

04

also known as (4)

Other names and identifiers for this entity.

05

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bdunvdNVDCVE.orgMITRE
published 2021-04-01modified 2026-06-17
07

references (9)

External citations — patches, advisories, analysis.

scry

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