Sceawere
Vulnerability Detail
CVE-2026-74363 Verified Sceawere Triage Sources: NVD / CISA KEV
Vulnerability Metadata
- Severity
- High
- Score / CVSS
- 7.8
- Creation Date
- 2d ago
- Vendor
- Linux
- Product
- Linux
- Attack Type
- N/A
- Vector String
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Attack Complexity
- LOW
Narrative and Response
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: fix UAF by restoring RCU-delayed inode freeing in bpffs commit 4f375ade6aa9 ("bpf: Avoid RCU context warning when unpinning htab with internal structs") moved inode cleanup from ->free_inode() into ->destroy_inode() to avoid sleeping in RCU context when calling bpf_any_put(). However this removed the RCU delay on freeing the inode itself and the cached symlink body (i_link), both of which can be accessed by RCU pathwalk (pick_link, may_lookup etc.). This causes a use-after-free when a concurrent unlinkat() drops the last inode reference and destroy_inode() frees the inode immediately, while another task is still walking the path in RCU mode and reads inode->i_opflags (offset +2) inside current_time() -> is_mgtime(). KASAN reports: BUG: KASAN: slab-use-after-free in is_mgtime include/linux/fs.h:2313 Read of size 2 at addr ffff8880407e4282 (offset +2 = i_opflags) The rules (per Al Viro): ->destroy_inode() called immediately, can sleep, use for blocking cleanup e.g. bpf_any_put() ->free_inode() called after RCU grace period, use for freeing inode and anything RCU-accessible e.g. i_link Fix: split the two concerns properly: - keep bpf_any_put() in bpf_destroy_inode() since it is blocking and needs to run promptly - introduce bpf_free_inode() to handle kfree(i_link) and free_inode_nonrcu() with proper RCU delay, preventing the UAF
Executive Summary
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Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
Technical Details
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.
Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
Mitigations
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Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
References
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Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
Additional Metadata
{
"score": "7.8",
"pubDate": "2026-08-15T06:22:37.900Z",
"pubdate": "2026-08-15T06:22:37.900Z"
}