CVE-2023-31926

System file overwrite via less command

Published Aug 2, 2023 · Updated Feb 13, 2025

Improper permission handling in the less command in Brocade Fabric OS before 9.1.1c and 9.2.0 allows local users to overwrite system files. Brocade has not disclosed how the less command preserves permissions or initializes file-handling state incorrectly. A low-privileged local account is required; successful exploitation can alter protected system data and disrupt the switch.

CVSS severity7.1
High
EPSS probability0.16%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper permission handling in the less command in Brocade Fabric OS before 9.1.1c and 9.2.0 allows local users to overwrite system files. Brocade has not disclosed how the less command preserves permissions or initializes file-handling state incorrectly. A low-privileged local account is required; successful exploitation can alter protected system data and disrupt the switch.

The record

CVE
CVE-2023-31926
Published
Aug 2, 2023
Updated
Feb 13, 2025
Vendor
Brocade Communications Systems
Product
Fabric OS
Classifications
CWE-281, CWE-665, T1565.001
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 2, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=before Brocade Fabric OS v9.1.1c and v9.2.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Brocade Communications Systems · Fabric OSversion=before Brocade Fabric OS v9.1.1c and v9.2.0

Published CVSS scores

7.1Brocade Communications Systems, LLCCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H

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)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-281Improper Preservation of Permissions
CWE-665Improper Initialization
T1565.001Stored Data Manipulation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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