CVE-2026-91203

Arbitrary file modification via privileged symlink race

Published Sep 18, 2026 · Updated Sep 18, 2026

Race condition in cockpit-files on Red Hat Enterprise Linux 9 allows local users to alter ownership or permissions on arbitrary files. During privileged ownership or permission changes, cockpit-files checks a target path and later acts on it without preventing replacement by a symlink. Exploitation requires a privileged Cockpit user to operate in an attacker-writable directory while the local attacker wins the timing race.

CVSS severity6.0
Medium
EPSS probability0.11%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Race condition in cockpit-files on Red Hat Enterprise Linux 9 allows local users to alter ownership or permissions on arbitrary files. During privileged ownership or permission changes, cockpit-files checks a target path and later acts on it without preventing replacement by a symlink. Exploitation requires a privileged Cockpit user to operate in an attacker-writable directory while the local attacker wins the timing race.

The record

CVE
CVE-2026-91203
Published
Sep 18, 2026
Updated
Sep 18, 2026
Vendor
Commonhaus Foundation
Product
Red Hat Enterprise Linux 9
Classifications
CWE-363, T1222.002
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 18, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 18, 2026Record 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?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Commonhaus Foundation · Red Hat Enterprise Linux 9Affected versions are unavailable in this record.

Published CVSS scores

6.0Red HatCVSS:3.1/AV:L/AC:H/PR:L/UI:R/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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-363Race Condition Enabling Link Following
T1222.002File and Directory Permissions Modification: Linux and Mac File and Directory Permissions Modification

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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