Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: fuse: avoid 32-bit prune notification count wrap FUSE_NOTIFY_PRUNE validates the nodeid payload length with: size - sizeof(outarg) != outarg.count * sizeof(u64) On 32-bit kernels, size_t is also 32 bits, so the daemon-controlled count multiplication can wrap. A prune notification with count 0x20000000 and no nodeid payload passes the check, enters the copy loop, and asks the device copy path to read nodeids that are not present in the userspace write buffer. In QEMU this reaches the fuse_copy_fill() BUG_ON(!err) path. Validate the payload length with array_size() instead. That accepts exactly the same valid messages, but avoids wrapping arithmetic before the copy loop consumes the count.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | >= 6.18, < 6.18.39 |
References
- https://git.kernel.org/stable/c/54243797cedf55447b4c5d560e8cd709900061aePatch
- https://git.kernel.org/stable/c/6e2d84fdeac05bfd858e84a76353fdb84f23a43ePatch
- https://git.kernel.org/stable/c/c78c4b242299bc581e4987e5c2786c6f4760c516Patch
FAQ
What is CVE-2026-64267?
CVE-2026-64267 is a vulnerability with a CVSS score of 5.5 (MEDIUM). In the Linux kernel, the following vulnerability has been resolved: fuse: avoid 32-bit prune notification count wrap FUSE_NOTIFY_PRUNE validates the nodeid payload length with: size - sizeof(ou...
How severe is CVE-2026-64267?
CVE-2026-64267 has been rated MEDIUM with a CVSS base score of 5.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-64267?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.