Bug 2507274 (CVE-2026-64261)

Summary: CVE-2026-64261 kernel: fuse-uring: Avoid use-after-free in fuse_uring_async_stop_queues
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: ---
Doc Text:
A flaw was found in the Linux kernel's `fuse-uring` component. This use-after-free vulnerability allows a local attacker to potentially achieve privilege escalation. The issue arises when the `fuse_uring_async_stop_queues()` function attempts to access memory that has already been freed, leading to unpredictable system behavior or unauthorized access. This flaw is mitigated by ensuring that a proper reference to the `fuse_conn` structure is maintained until the associated work queue has fully terminated.
 Story Points: ---
Clone Of: Environment:
Last Closed: Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-07-25 10:14:01 UTC 
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.
Comment 1 TEJ RATHI 2026-07-27 05:57:26 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026072557-CVE-2026-64261-71c6@gregkh/T