CVE-2026-31597
What it is
In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix use-after-free in ocfs2_fault() when VM_FAULT_RETRY filemap_fault() may drop the mmap_lock before returning VM_FAULT_RETRY, as documented in mm/filemap.c: "If our return value has VM_FAULT_RETRY set, it's because the mmap_lock may be dropped before doing I/O or by lock_folio_maybe_drop_mmap()." When this happens, a concurrent munmap() can call remove_vma() and free the vm_area_struct via RCU. The saved 'vma' pointer in ocfs2_fault() then becomes a dangling pointer, and the subsequent trace_ocfs2_fault() call dereferences it -- a use-after-free. Fix this by saving ip_blkno as a plain integer before calling filemap_fault(), and removing vma from the trace event. Since ip_blkno is copied by value before the lock can be dropped, it remains valid regardless of what happens to the vma or inode afterward.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.1% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.1% in the next 30 days (EPSS).
- Severity: 7.8 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.1% · EPSS, next 30 days
- Weakness
- CWE-416 · Use after free
- Record status
- Modified
Affected
- Linux Kernel < 6.6.136
- Linux Kernel < 6.12.83
- Linux Kernel < 6.18.24
- Linux Kernel < 6.19.14
- Linux Kernel < 7.0.1
Attack profile CVSS 3.1 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-31597.md and follow it. Check whether this project is affected by CVE-2026-31597. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/4cf2768a0291a0cdd0dae801ea0eafa3878a349d
- https://git.kernel.org/stable/c/6f072daefcab1d84ce37c073645615f63be91006
- https://git.kernel.org/stable/c/76a602fdbb78dd05b2da06f74a988cebc97e82d0
- https://git.kernel.org/stable/c/7de554cabf160e331e4442e2a9ad874ca9875921
- https://git.kernel.org/stable/c/925bf22c1b823e231b1baea761fe8a1512e442f2
- https://git.kernel.org/stable/c/d45ff441b416d4aa1af72b1db23d959601c04da2
References
- https://git.kernel.org/stable/c/35c2c05261d6f6d84aaa1355afa201d507943e76
- https://git.kernel.org/stable/c/36539c4d536f851a3b346a6ebb27b51bc3d77a94
- https://git.kernel.org/stable/c/3f5e74b5db9353b01ed50f4de84e75b755f8fbc2
- https://git.kernel.org/stable/c/4cf2768a0291a0cdd0dae801ea0eafa3878a349d
- https://git.kernel.org/stable/c/6f072daefcab1d84ce37c073645615f63be91006
- https://git.kernel.org/stable/c/76a602fdbb78dd05b2da06f74a988cebc97e82d0
- https://git.kernel.org/stable/c/7de554cabf160e331e4442e2a9ad874ca9875921
- https://git.kernel.org/stable/c/925bf22c1b823e231b1baea761fe8a1512e442f2
- https://git.kernel.org/stable/c/d45ff441b416d4aa1af72b1db23d959601c04da2