CVE-2026-63823

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.]

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-19 12:16

Updated : 2026-08-17 05:17

NVD link : CVE-2026-63823

Mitre link : CVE-2026-63823

CVE.ORG link : CVE-2026-63823

JSON object : View

Products Affected

No product.

CWE

No CWE.

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"unaffected", "version": "6.18.38", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.1.3", "versionType": "semver", "lessThanOrEqual": "7.1.*"}, {"status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["include/keys/request_key_auth-type.h", "security/keys/internal.h", "security/keys/keyctl.c", "security/keys/request_key_auth.c"], "defaultStatus": "affected"}]}], "published": "2026-07-19T12:16:55.457", "references": [{"url": "https://git.kernel.org/stable/c/35ab4db86774d82389e4b9559e26ab7f68d8e395", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/4982bfabce6b33b3c9eddb4fb900fe5568b7cf91", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/708709c65a1832a99b0eef8ae46e343ddaca3d06", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": 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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->target_key\n **USE-AFTER-FREE**\n\nGive request_key_auth payloads a refcount. Take a payload reference while\nauthkey->sem 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.]"}], "lastModified": "2026-08-17T05:17:19.800", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}