CVE-2023-53597 (GCVE-0-2023-53597)

Vulnerability from cvelistv5 – Published: 2025-10-04 15:44 – Updated: 2026-08-05 09:15
VLAI
Title
cifs: fix mid leak during reconnection after timeout threshold
Summary
In the Linux kernel, the following vulnerability has been resolved: cifs: fix mid leak during reconnection after timeout threshold When the number of responses with status of STATUS_IO_TIMEOUT exceeds a specified threshold (NUM_STATUS_IO_TIMEOUT), we reconnect the connection. But we do not return the mid, or the credits returned for the mid, or reduce the number of in-flight requests. This bug could result in the server->in_flight count to go bad, and also cause a leak in the mids. This change moves the check to a few lines below where the response is decrypted, even of the response is read from the transform header. This way, the code for returning the mids can be reused. Also, the cifs_reconnect was reconnecting just the transport connection before. In case of multi-channel, this may not be what we want to do after several timeouts. Changed that to reconnect the session and the tree too. Also renamed NUM_STATUS_IO_TIMEOUT to a more appropriate name MAX_STATUS_IO_TIMEOUT.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 8e670f77c4a55013db6d23b962f9bf6673a5e7b6 , < df31d05f0678cdd0796ea19983a2b93edca18bb0 (git)
Affected: 8e670f77c4a55013db6d23b962f9bf6673a5e7b6 , < c55901d381a22300c9922170e59704059f50977b (git)
Affected: 8e670f77c4a55013db6d23b962f9bf6673a5e7b6 , < 57d25e9905c71133e201f6d06b56a3403d4ad433 (git)
Affected: 8e670f77c4a55013db6d23b962f9bf6673a5e7b6 , < 69cba9d3c1284e0838ae408830a02c4a063104bc (git)
Affected: fa6d7a5853f93efb088aba36af12cb1944156411 (git)
Affected: 5.9.5 , < 5.10 (semver)
Create a notification for this product.
Linux Linux Affected: 5.10
Unaffected: 0 , < 5.10 (semver)
Unaffected: 5.15.150 , ≤ 5.15.* (semver)
Unaffected: 6.1.42 , ≤ 6.1.* (semver)
Unaffected: 6.4.7 , ≤ 6.4.* (semver)
Unaffected: 6.5 , ≤ * (original_commit_for_fix)
Create a notification for this product.
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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-04T19:16:52+00:00",
      "cve": "CVE-2023-53597",
      "id": "CVE-2023-53597",
      "initial_release_date": "2023-01-01T00:00:00+00:00",
      "product_status:fixed": "405",
      "product_status:known_not_affected": "115",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: cifs: fix mid leak during reconnection after timeout threshold",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2023/cve-2023-53597.json",
      "version": "3"
    },
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      "aggregate_severity": "moderate",
      "current_release_date": "2026-07-25T02:15:37Z",
      "cve": "CVE-2023-53597",
      "id": "CVE-2023-53597",
      "initial_release_date": "2025-10-05T02:55:42Z",
      "product_status:known_affected": "411",
      "product_status:known_not_affected": "82",
      "product_status:recommended": "585",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2023-53597",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2023-53597.json",
      "version": "50"
    }
  }
}



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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.

Sightings

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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.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • 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.