{"cve":"CVE-2025-68299","nvd":{"published":"2025-12-16T16:16:09.400","modified":"2026-10-14T16:10:00.250","status":"Deferred","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nafs: Fix delayed allocation of a cell's anonymous key\n\nThe allocation of a cell's anonymous key is done in a background thread\nalong with other cell setup such as doing a DNS upcall.  In the reported\nbug, this is triggered by afs_parse_source() parsing the device name given\nto mount() and calling afs_lookup_cell() with the name of the cell.\n\nThe normal key lookup then tries to use the key description on the\nanonymous authentication key as the reference for request_key() - but it\nmay not yet be set and so an oops can happen.\n\nThis has been made more likely to happen by the fix for dynamic lookup\nfailure.\n\nFix this by firstly allocating a reference name and attaching it to the\nafs_cell record when the record is created.  It can share the memory\nallocation with the cell name (unfortunately it can't just overlap the cell\nname by prepending it with \"afs@\" as the cell name already has a '.'\nprepended for other purposes).  This reference name is then passed to\nrequest_key().\n\nSecondly, the anon key is now allocated on demand at the point a key is\nrequested in afs_request_key() if it is not already allocated.  A mutex is\nused to prevent multiple allocation for a cell.\n\nThirdly, make afs_request_key_rcu() return NULL if the anonymous key isn't\nyet allocated (if we need it) and then the caller can return -ECHILD to\ndrop out of RCU-mode and afs_request_key() can be called.\n\nNote that the anonymous key is kind of necessary to make the key lookup\ncache work as that doesn't currently cache a negative lookup, but it's\nprobably worth some investigation to see if NULL can be used instead.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/5613bde937dfac6725e9c3fc766b9d6b8481e55b","https://git.kernel.org/stable/c/bd18d2cbc9377c6b270c0b7ea44b0e6ed1d99c07","https://git.kernel.org/stable/c/d27c71257825dced46104eefe42e4d9964bd032e"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:17:07.138532058+00:00"},"epss":{"cve":"CVE-2025-68299","score":0.00263,"percentile":0.17986,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}