What is CVE-2026-64386?

CVE-2026-64386 is a critical-severity vulnerability in Linux, classified under Double Free. CVSS score: 9.8/10. Published 2026-07-25.

How severe is CVE-2026-64386?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Double Free in Linux

CVE-2026-64386

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix query_info() replay double-free A response-bearing attempt can return a replayable error and free its response buffer. If SMB2_query_info_init() fails before the next send, cleanup retains the previous buffer type and frees that response again. Reset response bookkeeping before each attempt to prevent the stale free.

Vulnerability class: Double Free

EPSS: 0.005 (38.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Linux — versions 7.2-rc1, 6.6.145, 433042a91f9373241307725b52de573933ffedbf
Linux Linux_kernel — versions 6.8

Weakness classification (CWE)

CWE-415 — Double Free

References

416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)

Frequently asked questions

What is CVE-2026-64386?: CVE-2026-64386 is a critical-severity vulnerability in Linux, classified under Double Free. CVSS score: 9.8/10. Published 2026-07-25.
How severe is CVE-2026-64386?: Critical severity. CVSS v3 base score is 9.8 out of 10.