CVE-2026-64261: fuse-uring: Avoid use-after-free in fuse_uring_async_stop_queues

Greg Kroah-Hartman <[email protected]> Sat, 25 Jul 2026 10:47:58 +0200
Newsgroups org.kernel.vger.linux-cve-announce
Message-ID <2026072557-CVE-2026-64261-71c6@gregkh>
From: Greg Kroah-Hartman <[email protected]>

Description
===========

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

fuse-uring: Avoid use-after-free in fuse_uring_async_stop_queues

fuse_uring_async_stop_queues() might run when the last reference
on ring->queue_refs was already dropped.

In order to avoid an early destruction a reference on struct fuse_conn
is now taken before starting fuse_uring_async_stop_queues() and that
reference is only released when that delayed work queue terminates.

The Linux kernel CVE team has assigned CVE-2026-64261 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 6.14 with commit 4a9bfb9b6850fec0685447aed280533cf980de70 and fixed in 6.18.39 with commit 23a356e0bd96c8d5fb3ddff069f692bf10cab5c1
	Issue introduced in 6.14 with commit 4a9bfb9b6850fec0685447aed280533cf980de70 and fixed in 7.1.4 with commit 95d7f50aff2a5f71557263ff25b97b2951f32bf8
	Issue introduced in 6.14 with commit 4a9bfb9b6850fec0685447aed280533cf980de70 and fixed in 7.2-rc1 with commit d351da75066955144515cb2f9aa959f24a04287a

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-64261
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	fs/fuse/dev_uring.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/23a356e0bd96c8d5fb3ddff069f692bf10cab5c1
	https://git.kernel.org/stable/c/95d7f50aff2a5f71557263ff25b97b2951f32bf8
	https://git.kernel.org/stable/c/d351da75066955144515cb2f9aa959f24a04287a