{"id":"CVE-2026-63823","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-63823","generatedAt":"2026-10-28T07:05:22.943Z","title":"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…","description":"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->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.]","published":"2026-07-19T12:16:55.000Z","lastModified":"2026-10-22T18:40:16.000Z","status":"Analyzed","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":7.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-416"],"affected":["linux/linux kernel"],"epss":{"score":0.00161,"percentile":0.05199,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.16%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/35ab4db86774d82389e4b9559e26ab7f68d8e395","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/4982bfabce6b33b3c9eddb4fb900fe5568b7cf91","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/708709c65a1832a99b0eef8ae46e343ddaca3d06","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7216ce8cb12fee44e309503955bb83806b106129","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/83c0a1cb296d955d5f4d1f0bd8a769ba8ed8c29f","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d8274181b0f28d450b42489723a5ba81042158d7","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f9b68632ac93cc742f2e411021c4dbfe452ea0c2","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/fd15b457a86939c38aa12116adabd8ff686c5e51","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-63823","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}