CVE-2026-23268
CVE-2026-23268 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: High (CVSS 3.x base score 7.8)
- EPSS exploit prediction: 0% (3rd percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-12910
- Affected product: Linux Linux Kernel
- Published:
- Last modified:
Description
In the Linux kernel, the following vulnerability has been resolved: apparmor: fix unprivileged local user can do privileged policy management An unprivileged local user can load, replace, and remove profiles by opening the apparmorfs interfaces, via a confused deputy attack, by passing the opened fd to a privileged process, and getting the privileged process to write to the interface. This does require a privileged target that can be manipulated to do the write for the unprivileged process, but once such access is achieved full policy management is possible and all the possible implications that implies: removing confinement, DoS of system or target applications by denying all execution, by-passing the unprivileged user namespace restriction, to exploiting kernel bugs for a local privilege escalation. The policy management interface can not have its permissions simply changed from 0666 to 0600 because non-root processes need to be able to load policy to different policy namespaces. Instead ensure the task writing the interface has privileges that are a subset of the task that opened the interface. This is already done via policy for confined processes, but unconfined can delegate access to the opened fd, by-passing the usual policy check.
Frequently asked questions
- What is CVE-2026-23268?
- In the Linux kernel, the following vulnerability has been resolved: apparmor: fix unprivileged local user can do privileged policy management An unprivileged local user can load, replace, and remove profiles by opening the apparmorfs interfaces, via a confused deputy attack, by passing the opened fd to a privileged process, and getting the privileged process to write to the interface. This does require a privileged target that can be manipulated to do the write for the unprivileged process, but once such access is achieved full policy management is possible and all the possible implications that implies: removing confinement, DoS of system or target applications by denying all execution, by-passing the unprivileged user namespace restriction, to exploiting kernel bugs for a local privilege escalation. The policy management interface can not have its permissions simply changed from 0666 to 0600 because non-root processes need to be able to load policy to different policy namespaces. Instead ensure the task writing the interface has privileges that are a subset of the task that opened the interface. This is already done via policy for confined processes, but unconfined can delegate access to the opened fd, by-passing the usual policy check.
- How severe is CVE-2026-23268?
- CVE-2026-23268 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2026-23268 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-23268?
- CVE-2026-23268 primarily affects Linux Linux Kernel. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2026-23268?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2026-23268 have an EU (EUVD) identifier?
- Yes. CVE-2026-23268 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-12910.
- When was CVE-2026-23268 published?
- CVE-2026-23268 was published on 2026-03-18 and last updated on 2026-06-17.
References
- https://git.kernel.org/stable/c/0fc63dd9170643d15c25681fca792539e23f4640
- https://git.kernel.org/stable/c/17debf5586020790b5717f96e5e6a3ca5bb961ab
- https://git.kernel.org/stable/c/33ee909702e047c94aaf41d4eea35626d509802c
- https://git.kernel.org/stable/c/4cafce4d6d0a66ec27e3af5637c11901d60189fa
- https://git.kernel.org/stable/c/6601e13e82841879406bf9f369032656f441a425
- https://git.kernel.org/stable/c/a407a078cd41b5261b99d822af784bd9f136eb4d
- https://git.kernel.org/stable/c/b60b3f7a35c46b2e0ca934f9c988b8fca06d76c6
- https://git.kernel.org/stable/c/b6a94eeca9c6c8f7c55ad44c62c98324f51ec596
- https://www.qualys.com/2026/03/10/crack-armor.txt
Affected products (4)
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*
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