GHSA-HHF9-CXVJ-3MV7
Vulnerability from github – Published: 2026-07-19 12:30 – Updated: 2026-07-20 15:31In 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": [],
"aliases": [
"CVE-2026-63823"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-19T12:16:55Z",
"severity": "HIGH"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nkeys: Pin request_key_auth payload in instantiate paths\n\nA: request_key() B: KEYCTL_INSTANTIATE_IOV\n================ =========================\n\ncreate auth key\nstore rka in auth key\nwait for helper\n get auth key\n load rka from auth key\n copy user payload\n sleep on #PF\n\nhelper completed\ndetach and free rka\ndestroy auth key\n wake up\n use rka-\u003etarget_key\n **USE-AFTER-FREE**\n\nGive request_key_auth payloads a refcount. Take a payload reference while\nauthkey-\u003esem stabilizes the payload and revocation state. Hold that\nreference across the instantiate and reject paths. Drop the auth key\nowning reference from revoke and destroy.\n\n[jarkko: Replaced the first two paragraphs of text with an actual\n concurrency scenario.]",
"id": "GHSA-hhf9-cxvj-3mv7",
"modified": "2026-07-20T15:31:47Z",
"published": "2026-07-19T12:30:24Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-63823"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/35ab4db86774d82389e4b9559e26ab7f68d8e395"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/4982bfabce6b33b3c9eddb4fb900fe5568b7cf91"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/708709c65a1832a99b0eef8ae46e343ddaca3d06"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7216ce8cb12fee44e309503955bb83806b106129"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/83c0a1cb296d955d5f4d1f0bd8a769ba8ed8c29f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d8274181b0f28d450b42489723a5ba81042158d7"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f9b68632ac93cc742f2e411021c4dbfe452ea0c2"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/fd15b457a86939c38aa12116adabd8ff686c5e51"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
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