How severe is CVE-2021-43669?

CVE-2021-43669 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-43669 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43669?

CVE-2021-43669 primarily affects Linuxfoundation Fabric. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-43669?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-43669 published?

CVE-2021-43669 was published on 2021-11-18 and last updated on 2026-06-17.

CVE-2021-43669

CVE-2021-43669 is a high-severity vulnerability in Linuxfoundation Fabric with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-444.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-444
Affected product: Linuxfoundation Fabric
Published: 2021-11-18
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2021-43669?: 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.
How severe is CVE-2021-43669?: CVE-2021-43669 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-43669 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43669?: CVE-2021-43669 primarily affects Linuxfoundation Fabric. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-43669?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-43669 published?: CVE-2021-43669 was published on 2021-11-18 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:linuxfoundation:fabric:1.4.0:*:*:*:*:*:*:*
cpe:2.3:a:linuxfoundation:fabric:2.0.0:*:*:*:*:*:*:*
cpe:2.3:a:linuxfoundation:fabric:2.0.1:*:*:*:*:*:*:*
cpe:2.3:a:linuxfoundation:fabric:2.3.0:*:*:*:*:*:*:*

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