CVE-2026-74351 — ocfs2: rebase copied fsdlm LVB pointers in locking_state
In the Linux kernel, the following vulnerability has been resolved: ocfs2: rebase copied fsdlm LVB pointers in locking_state The locking_state debugfs iterator snapshots struct ocfs2_lock_res by value under ocfs2_dlm_tracking_lock and later formats that copy in ocfs2_dlm_seq_show(). That is fine for the inline fields, but the userspace fsdlm stack stores the LVB through lksb_fsdlm.sb_lvbptr. Once the iterator drops the tracking lock, a copied non-NULL sb_lvbptr still points into the original lockres owner, so teardown can free that container before the debugfs dump walks the raw LVB bytes. Rebase the copied sb_lvbptr to the copied l_lksb before dumping the raw LVB. The seq snapshot already carries the inline LVB storage reserved in struct ocfs2_dlm_lksb, so the debugfs reader can dump the copied bytes without borrowing the original lockres lifetime. The buggy scenario involves two paths, with each column showing the order within that path: locking_state reader: lockres teardown: 1. ocfs2_dlm_seq_start()/next() 1. file release or another owner copies struct ocfs2_lock_res teardown reaches 2. ocfs2_dlm_seq_show() formats ocfs2_lock_res_free() the copied row 2. the lockres is removed from the 3. ocfs2_dlm_lvb() follows the tracking list copied sb_lvbptr 3. the owner frees the original lockres container Validation reproduced this kernel report: KASAN slab-use-after-free in ocfs2_dlm_seq_show+0x1bd/0x430 RIP: 0033:0x7f8ec4b1e29d The buggy address belongs to the object at ffff88810a1e0800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 368 bytes inside of freed 1024-byte region [ffff88810a1e0800, ffff88810a1e0c00) Read of size 1 Call trace: dump_stack_lvl+0x66/0xa0 print_report+0xce/0x630 ocfs2_dlm_seq_show+0x1bd/0x430 (fs/ocfs2/dlmglue.c:3137) srso_alias_return_thunk+0x5/0xfbef5 __virt_addr_valid+0x19f/0x330 kasan_report+0xe0/0x110 seq_read_iter+0x29d/0x790 seq_read+0x20a/0x280 find_held_lock+0x2b/0x80 rcu_read_unlock+0x18/0x70 full_proxy_read+0x9e/0xd0 vfs_read+0x12c/0x590 ksys_read+0xd2/0x170 do_user_addr_fault+0x65a/0x890 do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87) entry_SYSCALL_64_after_hwframe+0x77/0x7f Allocated by task stack: kasan_save_stack+0x33/0x60 kasan_save_track+0x14/0x30 __kasan_kmalloc+0xaa/0xb0 ocfs2_file_open+0x13e/0x300 do_dentry_open+0x233/0x7f0 vfs_open+0x5a/0x1b0 path_openat+0x66d/0x1540 do_file_open+0x186/0x2b0 do_sys_openat2+0xce/0x150 __x64_sys_openat+0xd0/0x140 do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87) entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task stack: kasan_save_stack+0x33/0x60 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x60 __kasan_slab_free+0x5f/0x80 kfree+0x313/0x590 ocfs2_file_release+0x138/0x260 __fput+0x1df/0x4b0 fput_close_sync+0xd2/0x170 __x64_sys_close+0x55/0x90 do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87) entry_SYSCALL_64_after_hwframe+0x77/0x7f
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+2
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
≥ cf4d8d75d8aba537a19b313a9364fd08ddbd5622 and < 185427b5f7a209254c85c18aad5a4a8e009b2f30≥ cf4d8d75d8aba537a19b313a9364fd08ddbd5622 and < 07aa4a8ebacde3d0ba50f60d2964f274ee7629bc≥ cf4d8d75d8aba537a19b313a9364fd08ddbd5622 and < e037c1250cc90e7aacb002357d1b0399fc65ecfc≥ cf4d8d75d8aba537a19b313a9364fd08ddbd5622 and < 6b38a5b8ee951e5b244e9a3c3d28d0f5e7c51411≥ cf4d8d75d8aba537a19b313a9364fd08ddbd5622 and < 8614a8f7e81edd34c9f67e454e7024fd12a2a341≥ cf4d8d75d8aba537a19b313a9364fd08ddbd5622 and < bb44a7690a4d553da705919cf666a80f5ca9011c≥ cf4d8d75d8aba537a19b313a9364fd08ddbd5622 and < 610a0d2a35496738e1472fb0f318d5008a1c634f≥ cf4d8d75d8aba537a19b313a9364fd08ddbd5622 and < 93612d48fa42b3d1a637eb9279e15281c611c000 and 1 moreversion 2.6.26 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
EPSS over time FIRST
Oct 15, 2026 → Oct 29, 2026 · 14 reading(s) · max 0.22%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Not enough vector or weakness data: use the affected application’s logs as a starting point.
Timeline
What happened to this CVE, newest first.
- 2026
- Record published
- Affected products added · linux/linux
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
8 on the record
- git.kernel.org/stable/c/185427b5f7a209254c85c18aad5a4a8e009b2f30
- git.kernel.org/stable/c/93612d48fa42b3d1a637eb9279e15281c611c000
- git.kernel.org/stable/c/6b38a5b8ee951e5b244e9a3c3d28d0f5e7c51411
- git.kernel.org/stable/c/07aa4a8ebacde3d0ba50f60d2964f274ee7629bc
- git.kernel.org/stable/c/bb44a7690a4d553da705919cf666a80f5ca9011c
- git.kernel.org/stable/c/e037c1250cc90e7aacb002357d1b0399fc65ecfc
- git.kernel.org/stable/c/610a0d2a35496738e1472fb0f318d5008a1c634f
- git.kernel.org/stable/c/8614a8f7e81edd34c9f67e454e7024fd12a2a341
Elsewhere on this site
Related CVEs (same products)
- Unknown CVE-2026-99216 Drivers: hv: Don't reset VMBus connection state on error/exit paths 2d
- Unknown CVE-2026-99215 power: supply: core: prevent unregistering a power supply while a callback runs 2d
- Unknown CVE-2026-99207 scsi: target: Disable interrupts while holding delayed_cmd_lock 2d
- Unknown CVE-2026-99208 drm/xe/oa: Zero OA buffer at allocation 2d
- Unknown CVE-2026-99209 drm/xe: skip eviction of a BO with no resource 2d
- Unknown CVE-2026-99210 accel/rocket: clear rdev on device init failure 2d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CVSS score published by NVD, the CNA, CISA or GitHub so far.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-74351 is "ocfs2: rebase copied fsdlm LVB pointers in locking_state", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.22% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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