{"cve":"CVE-2026-74363","nvd":{"published":"2026-08-15T06:22:37.900","modified":"2026-10-16T19:17:41.930","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: fix UAF by restoring RCU-delayed inode freeing in bpffs\n\ncommit 4f375ade6aa9 (\"bpf: Avoid RCU context warning when unpinning\nhtab with internal structs\") moved inode cleanup from ->free_inode()\ninto ->destroy_inode() to avoid sleeping in RCU context when calling\nbpf_any_put(). However this removed the RCU delay on freeing the\ninode itself and the cached symlink body (i_link), both of which\ncan be accessed by RCU pathwalk (pick_link, may_lookup etc.).\n\nThis causes a use-after-free when a concurrent unlinkat() drops the\nlast inode reference and destroy_inode() frees the inode immediately,\nwhile another task is still walking the path in RCU mode and reads\ninode->i_opflags (offset +2) inside current_time() -> is_mgtime().\n\nKASAN reports:\n  BUG: KASAN: slab-use-after-free in is_mgtime include/linux/fs.h:2313\n  Read of size 2 at addr ffff8880407e4282 (offset +2 = i_opflags)\n\nThe rules (per Al Viro):\n  ->destroy_inode()  called immediately, can sleep, use for blocking\n                     cleanup e.g. bpf_any_put()\n  ->free_inode()     called after RCU grace period, use for freeing\n                     inode and anything RCU-accessible e.g. i_link\n\nFix: split the two concerns properly:\n  - keep bpf_any_put() in bpf_destroy_inode() since it is blocking\n    and needs to run promptly\n  - introduce bpf_free_inode() to handle kfree(i_link) and\n    free_inode_nonrcu() with proper RCU delay, preventing the UAF","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":[],"references":["https://git.kernel.org/stable/c/0497ff765746d9b2d17445c8f7cc737b36c0152a","https://git.kernel.org/stable/c/53649846e0437d1d9b7cb993cfe54c367addf7ae","https://git.kernel.org/stable/c/5fecb71c10c28aef276ba49c718dc961745fdcf0","https://git.kernel.org/stable/c/61f19729728243c82476dee31315143ed3275e7f","https://git.kernel.org/stable/c/b93c55b4932dd7e32dca8cf34a3443cc87a02906"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:49:10.689564601+00:00"},"epss":{"cve":"CVE-2026-74363","score":0.00126,"percentile":0.0223,"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."]}