How severe is CVE-2021-27794?

CVE-2021-27794 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-27794 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27794?

CVE-2021-27794 affects Broadcom Fabric Operating System. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27794?

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-2021-27794 published?

CVE-2021-27794 was published on 2021-08-12 and last updated on 2026-06-17.

CVE-2021-27794

CVE-2021-27794 is a high-severity vulnerability in Broadcom Fabric Operating System with a CVSS 3.x base score of 7.8. 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-287.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 4.6
EPSS exploit prediction: 0% (15th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Broadcom Fabric Operating System
Published: 2021-08-12
Last modified: 2026-06-17

Description

A vulnerability in the authentication mechanism of Brocade Fabric OS versions before Brocade Fabric OS v.9.0.1a, v8.2.3a and v7.4.2h could allow a user to Login with empty password, and invalid password through telnet, ssh and REST.

Frequently asked questions

What is CVE-2021-27794?: A vulnerability in the authentication mechanism of Brocade Fabric OS versions before Brocade Fabric OS v.9.0.1a, v8.2.3a and v7.4.2h could allow a user to Login with empty password, and invalid password through telnet, ssh and REST.
How severe is CVE-2021-27794?: CVE-2021-27794 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-27794 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27794?: CVE-2021-27794 affects Broadcom Fabric Operating System. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27794?: 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-2021-27794 published?: CVE-2021-27794 was published on 2021-08-12 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:broadcom:fabric_operating_system:*:*:*:*:*:*:*:*

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Other CWE-287 (Improper Authentication) vulnerabilities

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