VulnerabilityPublished 18 Sep 2026Updated 19 Oct 2026

CVE-2026-91205: Red Hat Enterprise Linux 9 · Race Condition Enabling Link Following

Affects Red Hat Enterprise Linux 9Source CVE Database V5

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Not known to be exploited · CVSS 6.0 Medium.

Data as of 2 Nov 2026, 10:58 UTC

CVSS 3.1 base score

6.0Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.1% chance of exploitation in 30 days – higher than 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N

Attack Vector: Local
Attack Complexity: High
Privileges Required: Low
User Interaction: Required
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: High: A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. For example, a successful attack may require an attacker to: gather knowledge about the environment in which the vulnerable target/component exists; prepare the target environment to improve exploit reliability; or inject themselves into the logical network path between the target and the resource requested by the victim in order to read and/or modify network communications (e.g., a man in the middle attack).
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 18 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2 Nov 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Red Hat Enterprise Linux 9cockpit-files	Affected–	Fixed in–
Red Hat Enterprise Linux 10cockpit-files	Affected–	Fixed in–

AI-suggested

Red Hat advises avoiding the privileged owner-assignment directory creation flow in cockpit-files within directories writable by untrusted local users. Administrators should restrict write permissions on shared parent directories. Where directories must remain writable and shared, applying the sticky bit is recommended to prevent users from replacing directory entries they do not own. Creating directories without owner assignment avoids the vulnerable privileged chown operation. A fix is being developed for actively maintained Red Hat Enterprise Linux and Fedora releases. For deferred streams (RHEL 9.6.z, RHEL 10.0.z, and Red Hat In-Vehicle OS), the fix is deferred due to moderate severity and exploitation difficulty, so mitigation relies on permission restrictions and usage practices.

Description

A race condition vulnerability exists in the cockpit-files package on Red Hat Enterprise Linux 9 and related distributions. A local unprivileged attacker with write access to a parent directory can replace a newly created directory with a symbolic link before the ownership change is applied, redirecting ownership changes to arbitrary files. This can lead to information disclosure or unauthorized modification of sensitive files such as /etc/shadow. Exploitation requires local access, an attacker-writable parent directory, user interaction, and winning a narrow race window. A fix is being developed for actively maintained releases, while some deferred streams will not receive immediate fixes due to moderate severity and exploitation difficulty. Mitigations include avoiding privileged owner-assignment directory creation in writable directories by untrusted users and applying the sticky bit on shared writable directories.

Impact

Successful exploitation allows a local unprivileged attacker to redirect ownership changes to arbitrary files, potentially gaining unauthorized access or modification rights to sensitive system files such as /etc/shadow. This can lead to information disclosure and unauthorized file modifications. However, exploitation is constrained by the need for local access, writable parent directory control, user interaction, and winning a race condition, limiting the practical impact to specific scenarios.

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Affected software

Description

AI analysisMachine-generated, updated 25 Oct 2026, 01:14 UTC

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