CVE-2026-64383
In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix double-free in SMB2_flush() replay
SMB2_flush() keeps its response buffer bookkeeping across replay
attempts. If a replayable flush response is received and the retry then
fails before cifs_send_recv() stores a replacement response, flush_exit
will free the stale response pointer a second time.
Reinitialize resp_buftype and rsp_iov at the top of the replay loop so
cleanup only acts on response state produced by the current attempt.
This fixes a double-free without changing replay handling for successful
requests.
CSIRTS triage
- What
- There is a double-free vulnerability in the SMB2_flush() function during replay operations.
- Who is affected
- Deployments of the Linux kernel with SMB2 functionality may be affected.
- Urgency
- Remediation is important to prevent potential memory corruption, though exploitation is not currently known.
- Action
- Monitor for updates regarding this issue.
AI-assisted analysis generated from the source advisory — verify against the original.
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Exploitation outlook
- Low exploitation risk0.46% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 37% of all EPSS-scored CVEs.
Advisory coverage (2)
- criticalCVE-2026-64383: In the Linux kernel, the following vulnerability has been resolved: smb: client: fix double-fr…nvd · 2026-07-25
- highCVE-2026-64383: smb: client: fix double-free in SMB2_flush() replaymsrc · 2026-07-14
External references
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