In the Linux kernel, the following vulnerability has been resolved: smb: client: fix double-free in SMB2_ioctl() replay A response-bearing attempt… (CVE-2026-64385)
A double-free vulnerability in the Linux kernel SMB client was resolved. The issue occurs in the SMB2_ioctl() function where a response-bearing attempt can return a replayable error and free its response buffer. If SMB2_ioctl_init() fails before the next send, the cleanup process frees the same response buffer again due to stale bookkeeping. The fix resets response bookkeeping before each attempt to prevent this double-free condition.
AI Analysis
Technical Summary
The vulnerability in the Linux kernel SMB client involves a double-free in the SMB2_ioctl() function. Specifically, when a response-bearing attempt returns a replayable error and frees its response buffer, a subsequent failure in SMB2_ioctl_init() can cause the cleanup routine to free the same buffer again because it retains stale buffer type information. This double-free can lead to memory corruption or instability. The patch addresses this by resetting the response bookkeeping before each attempt to avoid freeing the same buffer twice.
Potential Impact
The double-free vulnerability can cause memory corruption in the Linux kernel SMB client, potentially leading to system instability or crashes. No known exploits in the wild have been reported. The impact is limited to the SMB client component of the Linux kernel.
Mitigation Recommendations
A fix for this vulnerability has been implemented in the Linux kernel. Users should update to the patched kernel version once available. Patch status is not explicitly confirmed in the provided data; therefore, check the official Linux kernel advisories or vendor updates for the exact fixed versions and apply the official patch accordingly.
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix double-free in SMB2_ioctl() replay A response-bearing attempt… (CVE-2026-64385)
Description
A double-free vulnerability in the Linux kernel SMB client was resolved. The issue occurs in the SMB2_ioctl() function where a response-bearing attempt can return a replayable error and free its response buffer. If SMB2_ioctl_init() fails before the next send, the cleanup process frees the same response buffer again due to stale bookkeeping. The fix resets response bookkeeping before each attempt to prevent this double-free condition.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in the Linux kernel SMB client involves a double-free in the SMB2_ioctl() function. Specifically, when a response-bearing attempt returns a replayable error and frees its response buffer, a subsequent failure in SMB2_ioctl_init() can cause the cleanup routine to free the same buffer again because it retains stale buffer type information. This double-free can lead to memory corruption or instability. The patch addresses this by resetting the response bookkeeping before each attempt to avoid freeing the same buffer twice.
Potential Impact
The double-free vulnerability can cause memory corruption in the Linux kernel SMB client, potentially leading to system instability or crashes. No known exploits in the wild have been reported. The impact is limited to the SMB client component of the Linux kernel.
Mitigation Recommendations
A fix for this vulnerability has been implemented in the Linux kernel. Users should update to the patched kernel version once available. Patch status is not explicitly confirmed in the provided data; therefore, check the official Linux kernel advisories or vendor updates for the exact fixed versions and apply the official patch accordingly.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-w5jf-frgq-phfp
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-64385"]
- Ecosystems
- []
- Database Specific Severity
- null
- Cvss Version
- null
Threat ID: 6a65420a9c2644c7f808444f
Added to database: 07/25/2026, 23:08:58 UTC
Last enriched: 07/25/2026, 23:27:42 UTC
Last updated: 07/26/2026, 03:43:34 UTC
Views: 4
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