Critical severity · published Aug 6, 2026
CVE-2026-64597
smb: client: fix double-free in SMB2_close() replay
9.8
CVSS
0.4%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 29% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
433042a91f9373241307725b52de573933ffedbf before 037511726228aaf165c7067ff2bfc88eaecdf1f3; 4f1fffa2376922f3d1d506e49c0fd445b023a28e before 0aa97edf7c347c0f54e7e60c4740574b8120c66a; 4f1fffa2376922f3d1d506e49c0fd445b023a28e before d15d83125007f673aec4323e1bbbaaffbe87ea13; 4f1fffa2376922f3d1d506e49c0fd445b023a28e before b18ed621dbfceecea5539848cddcb9272c9a61e1; 4f1fffa2376922f3d1d506e49c0fd445b023a28e before f96e1cdcb63ed3321142ff2fcdf784e32cda8fee; 6.6.32 before 6.6.145; +1 more · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-64597
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-64597
git.kernel.org
https://git.kernel.org/stable/c/037511726228aaf165c7067ff2bfc88eaecdf1f3
git.kernel.org
https://git.kernel.org/stable/c/0aa97edf7c347c0f54e7e60c4740574b8120c66a
git.kernel.org
https://git.kernel.org/stable/c/b18ed621dbfceecea5539848cddcb9272c9a61e1
git.kernel.org
https://git.kernel.org/stable/c/d15d83125007f673aec4323e1bbbaaffbe87ea13
git.kernel.org
https://git.kernel.org/stable/c/f96e1cdcb63ed3321142ff2fcdf784e32cda8fee
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