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-2026-64267MEDIUM
Linux Linux — fuse: avoid 32-bit prune notification count wrap
  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    3f29d59e92a96d843c2ff10ebfed92ac26878658 –  —
  Linux    6.18 –                                      6.18.39
TIMELINE
  Jul 19  Reserved by Linux
  Jul 25  Published (CNA: Linux)
  Aug 17  ENRICHED — CVE-2026-64267 (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: avoid 32-bit prune notification count wrap FUSE_NOTIFY_PRUNE validates the nodeid payload length with: size - sizeof(outarg) != outarg.count * sizeof(u64) On 32-bit kernels, size_t is also 32 bits, so the daemon-controlled count multiplication can wrap. A prune notification with count 0x20000000 and no nodeid payload passes the check, enters the copy loop, and asks the device copy path to read nodeids that are not present in the userspace write buffer. In QEMU this reaches the fuse_copy_fill() BUG_ON(!err) path. Validate the payload length with array_size() instead. That accepts exactly the same valid messages, but avoids wrapping arithmetic before the copy loop consumes the count.

Lifecycle

Complete event history — 3 events, chronological
DateEventDetail
July 19, 2026ReservedReserved by Linux
July 25, 2026PublishedPublished (CNA: Linux)
August 17, 2026ENRICHEDENRICHED — CVE-2026-64267 (Linux). Received CVSS 5.5 and CPE data from NVD.

Affected

Affected products and packages — 2 rows
VendorProduct / PackageEcosystemVersion introducedFixed
LinuxLinux3f29d59e92a96d843c2ff10ebfed92ac26878658
LinuxLinux6.186.18.39

References (3)

Related

Authoritative record: CVE-2026-64267 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-2026-64267 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.