CVE-2021-27796Network attack vector

Arbitrary file disclosure via restricted-shell binaries

Published Feb 21, 2022 · Updated Aug 3, 2024

File disclosure in the shell of Brocade Fabric OS before 8.0.1b and 7.4.1d allows remote authenticated users to read any file. Several binaries available inside rbash read files beyond the account's intended filesystem restrictions. Access requires a valid user or factory account, and exploitation discloses complete filesystem contents without reported modification or service interruption.

CVSS severity6.5
Medium
EPSS probability0.91%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

File disclosure in the shell of Brocade Fabric OS before 8.0.1b and 7.4.1d allows remote authenticated users to read any file. Several binaries available inside rbash read files beyond the account's intended filesystem restrictions. Access requires a valid user or factory account, and exploitation discloses complete filesystem contents without reported modification or service interruption.

The record

CVE
CVE-2021-27796
Published
Feb 21, 2022
Updated
Aug 3, 2024
Vendor
Brocade Communications Systems
Product
Brocade Fabric OS
Classifications
T1005
Attack vector
network
Privileges
authenticated

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 versions before Brocade Fabric OS v8.0.1b, v7.4.1d

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Brocade Communications Systems · Brocade Fabric OSversion=Brocade Fabric OS versions before Brocade Fabric OS v8.0.1b, v7.4.1d

Published CVSS scores

6.8NIST NVDAV:N/AC:L/Au:S/C:C/I:N/A:N
6.5Brocade Communications SystemsCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1005Data from Local System

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

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Your stack

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