No exploitation reportedFix available

CVE-2021-43669

Q: Is CVE-2021-43669 actively exploited?

Active exploitation of CVE-2021-43669 has not been confirmed. Its EPSS score was 1.1% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2021-43669?

CVE-2021-43669 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

No exploitation reported by the sources we read.

Published2021-11-18
WeaknessCWE-444

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

A vulnerability has been detected in HyperLedger Fabric v1.4.0, v2.0.0, v2.0.1, v2.3.0. It can easily break down as many orderers as the attacker wants. This bug can be leveraged by constructing a message whose header is invalid to the interface Order. This bug has been admitted and fixed by the developers of Fabric.

Timeline

dates in UTC

2021-11-1816:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-43669?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-43669?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD · OSV

Linuxfoundation fabric

Branch	Affected	Fixed in	Source
1.4	= 1.4.0	no fix published	NVD
2.0	= 2.0.0	no fix published	NVD
2.0	= 2.0.1	no fix published	NVD
2.3	= 2.3.0	no fix published	NVD

hyperledger/fabric

Branch	Affected	Fixed in	Source
2.4	< 2.4.0	2.4.0	OSV

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Advisories and patches

github.comPatch
jira.hyperledger.orgVendor Advisory

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVSS 3.17.5read 2026-10-23
NVDCVSS 2.05read 2026-10-23
NVDweakness (CWE)CWE-444read 2026-10-23
FIRST EPSSEPSS score1.1 %2026-10-23
OSVaffected packages—

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: 2021-11-18
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2021-43669?

Is CVE-2021-43669 actively exploited?

Active exploitation of CVE-2021-43669 has not been confirmed. Its EPSS score was 1.1% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-43669?

CVE-2021-43669 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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