Double Free in Linux

CVE-2026-64597

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix double-free in SMB2_close() replay A response-bearing attempt can return a replayable error and free its response buffer. If SMB2_close_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

Published · last modified .

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.

EPSS exploit prediction

EPSS: 0.004 (29.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 30th percentile — 29.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-64597: held from 0.007 to 0.004.

EPSS over last 30 days · oldest: 0.007 · newest: 0.004 · change: -0.003

Affected products

  • Linux — versions 7.2-rc1, 6.6.145, 433042a91f9373241307725b52de573933ffedbf

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-64597?
CVE-2026-64597 is a critical-severity vulnerability in Linux, classified under Double Free. CVSS score: 9.8/10. Published 2026-08-06.
How severe is CVE-2026-64597?
Critical severity. CVSS v3 base score is 9.8 out of 10.