CVE-2026-31609 (GCVE-0-2026-31609)

Vulnerability from cvelistv5 – Published: 2026-04-24 14:42 – Updated: 2026-08-05 12:23
VLAI
Title
smb: client: avoid double-free in smbd_free_send_io() after smbd_send_batch_flush()
Summary
In the Linux kernel, the following vulnerability has been resolved: smb: client: avoid double-free in smbd_free_send_io() after smbd_send_batch_flush() smbd_send_batch_flush() already calls smbd_free_send_io(), so we should not call it again after smbd_post_send() moved it to the batch list.
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: cca0526ef2344cab6944d7f441fc24e152da031b , < a9940dcbe5cb92482c04efc7341039ddf7dbf607 (git)
Affected: 37b5c06956183b65e6808b509cf637632016cdf7 , < 22b7c1c619d808aec4cad3dc42103345e370d107 (git)
Affected: 21538121efe6c8c5b51c742fa02cbe820bc48714 , < f9a162c2bbcd0ac85bd07c5b37cf20286048b65c (git)
Affected: 21538121efe6c8c5b51c742fa02cbe820bc48714 , < 27b7c3e916218b5eb2ee350211140e961bfc49be (git)
Affected: 6.18.11 , < 6.18.24 (semver)
Affected: 6.19.1 , < 6.19.14 (semver)
guessed Create a notification for this product.
Linux Linux Affected: 7.0
Unaffected: 0 , < 7.0 (semver)
Unaffected: 6.18.24 , ≤ 6.18.* (semver)
Unaffected: 6.19.14 , ≤ 6.19.* (semver)
Unaffected: 7.0.1 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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      "title": "smb: client: avoid double-free in smbd_free_send_io() after smbd_send_batch_flush()",
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      "title": "kernel: smb: client: avoid double-free in smbd_free_send_io() after smbd_send_batch_flush()",
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      "status": "interim",
      "title": "SUSE CVE CVE-2026-31609",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-31609.json",
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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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Nomenclature

  • 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.



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