CVE-2026-63823
What it is
In the Linux kernel, the following vulnerability has been resolved: keys: Pin request_key_auth payload in instantiate paths A: request_key() B: KEYCTL_INSTANTIATE_IOV ================ ========================= create auth key store rka in auth key wait for helper get auth key load rka from auth key copy user payload sleep on #PF helper completed detach and free rka destroy auth key wake up use rka->target_key **USE-AFTER-FREE** Give request_key_auth payloads a refcount. Take a payload reference while authkey->sem stabilizes the payload and revocation state. Hold that reference across the instantiate and reject paths. Drop the auth key owning reference from revoke and destroy. [jarkko: Replaced the first two paragraphs of text with an actual concurrency scenario.]
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.2% in the next 30 days (EPSS).
- Severity: 7.8 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Weakness
- CWE-416 · Use after free
- Record status
- Analyzed
Affected
- Linux Kernel < 5.10.260
- Linux Kernel < 5.15.211
- Linux Kernel < 6.1.177
- Linux Kernel < 6.6.144
- Linux Kernel < 6.12.95
- Linux Kernel < 6.18.38
- Linux Kernel < 7.1.3
Attack profile CVSS 3.1 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-63823.md and follow it. Check whether this project is affected by CVE-2026-63823. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/35ab4db86774d82389e4b9559e26ab7f68d8e395
- https://git.kernel.org/stable/c/4982bfabce6b33b3c9eddb4fb900fe5568b7cf91
- https://git.kernel.org/stable/c/708709c65a1832a99b0eef8ae46e343ddaca3d06
- https://git.kernel.org/stable/c/7216ce8cb12fee44e309503955bb83806b106129
- https://git.kernel.org/stable/c/83c0a1cb296d955d5f4d1f0bd8a769ba8ed8c29f
- https://git.kernel.org/stable/c/d8274181b0f28d450b42489723a5ba81042158d7
- https://git.kernel.org/stable/c/f9b68632ac93cc742f2e411021c4dbfe452ea0c2
- https://git.kernel.org/stable/c/fd15b457a86939c38aa12116adabd8ff686c5e51
References
- https://git.kernel.org/stable/c/35ab4db86774d82389e4b9559e26ab7f68d8e395
- https://git.kernel.org/stable/c/4982bfabce6b33b3c9eddb4fb900fe5568b7cf91
- https://git.kernel.org/stable/c/708709c65a1832a99b0eef8ae46e343ddaca3d06
- https://git.kernel.org/stable/c/7216ce8cb12fee44e309503955bb83806b106129
- https://git.kernel.org/stable/c/83c0a1cb296d955d5f4d1f0bd8a769ba8ed8c29f
- https://git.kernel.org/stable/c/d8274181b0f28d450b42489723a5ba81042158d7
- https://git.kernel.org/stable/c/f9b68632ac93cc742f2e411021c4dbfe452ea0c2
- https://git.kernel.org/stable/c/fd15b457a86939c38aa12116adabd8ff686c5e51