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CVE-2026-64383 (GCVE-0-2026-64383)

Vulnerability from cvelistv5 – Published: 2026-07-25 08:50 – Updated: 2026-08-17 04:54
VLAI
Title
smb: client: fix double-free in SMB2_flush() replay
Summary
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.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 433042a91f9373241307725b52de573933ffedbf , < 6e27f40b682a5e42a2daae3ce6d96f0e0e16dedb (git)
Affected: 4f1fffa2376922f3d1d506e49c0fd445b023a28e , < 878757163eea684750107a31ea134c103863515d (git)
Affected: 4f1fffa2376922f3d1d506e49c0fd445b023a28e , < 3407240cde132a4b72d6429a2625a09a2f78adaf (git)
Affected: 4f1fffa2376922f3d1d506e49c0fd445b023a28e , < 013a9a3da46c5dabcf18f65ea6a47874ba12a15d (git)
Affected: 4f1fffa2376922f3d1d506e49c0fd445b023a28e , < 4be31c943a3a27a5a0251dbb8f5cb89059ec3d5a (git)
Affected: 6.6.32 , < 6.6.145 (semver)
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Linux Linux Affected: 6.8
Unaffected: 0 , < 6.8 (semver)
Unaffected: 6.6.145 , ≤ 6.6.* (semver)
Unaffected: 6.12.96 , ≤ 6.12.* (semver)
Unaffected: 6.18.39 , ≤ 6.18.* (semver)
Unaffected: 7.1.4 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.