CVE-2026-31716
What it is
In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: validate rec->used in journal-replay file record check check_file_record() validates rec->total against the record size but never validates rec->used. The do_action() journal-replay handlers read rec->used from disk and use it to compute memmove lengths: DeleteAttribute: memmove(attr, ..., used - asize - roff) CreateAttribute: memmove(..., attr, used - roff) change_attr_size: memmove(..., used - PtrOffset(rec, next)) When rec->used is smaller than the offset of a validated attribute, or larger than the record size, these subtractions can underflow allowing us to copy huge amounts of memory in to a 4kb buffer, generally considered a bad idea overall. This requires a corrupted filesystem, which isn't a threat model the kernel really needs to worry about, but checking for such an obvious out-of-bounds value is good to keep things robust, especially on journal replay Fix this up by bounding rec->used correctly. This is much like commit b2bc7c44ed17 ("fs/ntfs3: Fix slab-out-of-bounds read in DeleteIndexEntryRoot") which checked different values in this same switch statement.
At a glance
- Exploitability
- Can be exploited locally on the machine without logging in, but needs a user to act. 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-787 · Out-of-bounds write
- Record status
- Modified
Affected
- Linux Kernel < 6.6.136
- Linux Kernel < 6.12.84
- Linux Kernel < 6.18.25
- Linux Kernel < 7.0.2
- Linux Kernel 7.1
Attack profile CVSS 3.1 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/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-2026-31716.md and follow it. Check whether this project is affected by CVE-2026-31716. 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/0112e6279420d4005b3d57af36fb45c01b8d0116
- https://git.kernel.org/stable/c/0ca0485e4b2e837ebb6cbd4f2451aba665a03e4b
- https://git.kernel.org/stable/c/4b1613d7e2deda831a97e427d1ea586e50fe1be5
- https://git.kernel.org/stable/c/f79d0403ea20a81bc29105bba54fbcab54e8c403
- https://git.kernel.org/stable/c/f90b8a1798b750755a9e9aee66678f0a1820bbaf
References
- https://git.kernel.org/stable/c/0112e6279420d4005b3d57af36fb45c01b8d0116
- https://git.kernel.org/stable/c/0ca0485e4b2e837ebb6cbd4f2451aba665a03e4b
- https://git.kernel.org/stable/c/1393a467a9607e62123806de7d4c3a3e54e396a9
- https://git.kernel.org/stable/c/4b1613d7e2deda831a97e427d1ea586e50fe1be5
- https://git.kernel.org/stable/c/8e64d33198b5a0fb14a452708bad844f94f03b2c
- https://git.kernel.org/stable/c/f79d0403ea20a81bc29105bba54fbcab54e8c403
- https://git.kernel.org/stable/c/f90b8a1798b750755a9e9aee66678f0a1820bbaf