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.
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.
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
| Date | Event | Detail |
| July 19, 2026 | Reserved | Reserved by Linux |
| July 25, 2026 | Published | Published (CNA: Linux) |
| August 17, 2026 | ENRICHED | ENRICHED — CVE-2026-64263 (Linux). Received CVSS 5.5 and CPE data from NVD. |
Affected
Affected products and packages — 2 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
| Linux | Linux | — | 4fea593e625cd50d4d11be227007849b12f17bfb | — |
| Linux | Linux | — | 6.16 | 6.18.39 |
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.