CVE-2026-64258 fuse-uring: remove request-less entries from ent_w_req_queue to fix NULL deref

What is CVE-2026-64258?

CVE-2026-64258 is a medium-severity vulnerability in Linux kernel, published on 25 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

fuse-uring: remove request-less entries from ent_w_req_queue to fix NULL deref

If a copy into the userspace ring buffer fails, a request will be terminated and fuse_uring_req_end() will set ent->fuse_req to NULL but it will leave the entry on ent_w_req_queue in FRRS_FUSE_REQ state. This can lead to a NULL deref if the request expiration logic scans ent_w_req_queue in the window before the entry is moved off it.

Fix this by taking the entry off ent_w_req_queue and changing its state from FRRS_FUSE_REQ to FRRS_INVALID before terminating the request.

Weakness: CWE-476

Which versions are affected by CVE-2026-64258?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-64258?

Apply the vendor's patch.

Is CVE-2026-64258 being exploited?

There is no known exploitation of CVE-2026-64258 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2026-64258, DEBIAN-CVE-2026-64258, GHSA-942f-2j62-7hwj, ROOT-OS-UBUNTU-2204-CVE-2026-64258, UBUNTU-CVE-2026-64258.