boxscore/security
CVE · referencelatest edition

Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-64263MEDIUM
Linux Linux — fuse-uring: fix moving cancelled entry to ent_in_userspace list
  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   L   L   L   N  U  N  N  H    5.5   .0015    5.0     —
AFFECTED
  Product  Versions                                    Fixed
  Linux    4fea593e625cd50d4d11be227007849b12f17bfb –  —
  Linux    6.16 –                                      6.18.39
TIMELINE
  Jul 19  Reserved by Linux
  Jul 25  Published (CNA: Linux)
  Aug 17  ENRICHED — CVE-2026-64263 (Linux). Received CVSS 5.5 and CPE data from NVD.
CNA: Linux · CVSS v3.1 · 3 references · NVD status: Analyzed

Description

In the Linux kernel, the following vulnerability has been resolved: fuse-uring: fix moving cancelled entry to ent_in_userspace list fuse_uring_cancel() moves entries that are available (these have no reqs attached) to the ent_in_userspace list. ent_list_request_expired() checks the first entry on ent_in_userspace and dereferences ent->fuse_req unconditionally, which will crash on a cancelled entry that was moved to this list. Fix this by freeing the entry and dropping queue_refs directly in fuse_uring_cancel(). This is safe because cancel is the cancel handler itself - after io_uring_cmd_done(), no more cancels will be dispatched for this command, and teardown serializes with cancel via queue->lock. Since cancel now decrements queue_refs, fuse_uring_abort() must no longer gate fuse_uring_abort_end_requests() on queue_refs > 0, as cancelled entries may have already dropped queue_refs while requests are still queued. Remove the gate so abort always flushes requests and stops queues.

Lifecycle

Complete event history — 3 events, chronological
DateEventDetail
July 19, 2026ReservedReserved by Linux
July 25, 2026PublishedPublished (CNA: Linux)
August 17, 2026ENRICHEDENRICHED — CVE-2026-64263 (Linux). Received CVSS 5.5 and CPE data from NVD.

Affected

Affected products and packages — 2 rows
VendorProduct / PackageEcosystemVersion introducedFixed
LinuxLinux4fea593e625cd50d4d11be227007849b12f17bfb
LinuxLinux6.166.18.39

References (3)

Related

Authoritative record: CVE-2026-64263 at cve.org

Vendors: linux

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-64263 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.