CVE-2021-27797Network attack vector

Unauthenticated switch access via bypassable password-change prompt

Published Feb 21, 2022 · Updated Aug 3, 2024

Hard-coded credentials in Brocade Fabric OS before 8.2.1c or 8.1.2h allow remote attackers to access switches over the network. The factory accounts use the documented password “password,” and affected releases permit the initial-login password-change prompt to be bypassed. Network access to a switch management service is sufficient; successful login grants the privileges assigned to the unchanged default account.

CVSS severity7.5
High
EPSS probability1.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Hard-coded credentials in Brocade Fabric OS before 8.2.1c or 8.1.2h allow remote attackers to access switches over the network. The factory accounts use the documented password “password,” and affected releases permit the initial-login password-change prompt to be bypassed. Network access to a switch management service is sufficient; successful login grants the privileges assigned to the unchanged default account.

The record

CVE
CVE-2021-27797
Published
Feb 21, 2022
Updated
Aug 3, 2024
Vendor
Brocade Communications Systems
Product
Brocade Fabric OS
Classifications
CWE-798, T1078.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 21, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Brocade Fabric OS before Brocade Fabric OS v8.2.1c, v8.1.2h, and all versions of Brocade Fabric OS v8.0.x and v7.x

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Brocade Communications Systems · Brocade Fabric OSversion=Brocade Fabric OS before Brocade Fabric OS v8.2.1c, v8.1.2h, and all versions of Brocade Fabric OS v8.0.x and v7.x

Published CVSS scores

7.5Brocade Communications SystemsCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-798Use of Hard-coded Credentials
T1078.001Valid Accounts: Default Accounts

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo