Description
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.]
Affected products
linux: linux kernel
References8
- git.kernel.org/stable/c/35ab4db86774d82389e4b9559e26ab7f68d8e395 Patch
- git.kernel.org/stable/c/4982bfabce6b33b3c9eddb4fb900fe5568b7cf91 Patch
- git.kernel.org/stable/c/708709c65a1832a99b0eef8ae46e343ddaca3d06 Patch
- git.kernel.org/stable/c/7216ce8cb12fee44e309503955bb83806b106129 Patch
- git.kernel.org/stable/c/83c0a1cb296d955d5f4d1f0bd8a769ba8ed8c29f Patch
- git.kernel.org/stable/c/d8274181b0f28d450b42489723a5ba81042158d7 Patch
- git.kernel.org/stable/c/f9b68632ac93cc742f2e411021c4dbfe452ea0c2 Patch
- git.kernel.org/stable/c/fd15b457a86939c38aa12116adabd8ff686c5e51 Patch
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 5 · as of 14 November 2026
- CWE
- CWE-416
Could this be exploited in your environment?
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