CVE-2023-52757

System hang via SMB client lock inversion

Published May 21, 2024 · Updated May 23, 2026

Improper locking in affected Linux kernel SMB clients allows local users to hang the system by triggering concurrent MID release. release_mid() calls kref_put() while holding server->mid_lock, and __release_mid() then takes cifs_tcp_ses_lock opposite cifs_debug_data_proc_show(). Reachability requires low-privileged local access, an active SMB client context, and the competing debug-data path; successful triggering deadlocks the kernel and hangs the system.

CVSS severity7.8
High
EPSS probability0.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper locking in affected Linux kernel SMB clients allows local users to hang the system by triggering concurrent MID release. release_mid() calls kref_put() while holding server->mid_lock, and __release_mid() then takes cifs_tcp_ses_lock opposite cifs_debug_data_proc_show(). Reachability requires low-privileged local access, an active SMB client context, and the competing debug-data path; successful triggering deadlocks the kernel and hangs the system.

The record

CVE
CVE-2023-52757
Published
May 21, 2024
Updated
May 23, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-416, CWE-667
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 21, 2024CVE publishedPublication date reported by the CVE source.
  2. May 23, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=5.4.6 <5.5
  2. Affected versionversion=5.5
  3. Affected versionversion=7b71843fa7028475b052107664cbe120156a2cfc <99f476e27aad5964ab13777d84fda67d1356dec1
  4. Affected versionversion=7b71843fa7028475b052107664cbe120156a2cfc <9eb44db68c5b7f5aa22b8fc7de74a3e2e08d1f29
  5. Affected versionversion=7b71843fa7028475b052107664cbe120156a2cfc <b9bb9607b1fc12fca51f5632da25b36975f599bf
  6. Affected versionversion=7b71843fa7028475b052107664cbe120156a2cfc <c1a5962f1462b64fe7b69f20a4b6af8067bc2d26
  7. Affected versionversion=7b71843fa7028475b052107664cbe120156a2cfc <ce49569079a9d4cad26c0f1d4653382fd9a5ca7a
  8. Affected versionversion=7b71843fa7028475b052107664cbe120156a2cfc <e6322fd177c6885a21dd4609dc5e5c973d1a2eb7
  9. Affected versionversion=9871dea42034ee6e73bb2b97ba0284d3d462b230

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5.4.6 <5.5; version=5.5; version=7b71843fa7028475b052107664cbe120156a2cfc <99f476e27aad5964ab13777d84fda67d1356dec1; version=7b71843fa7028475b052107664cbe120156a2cfc <9eb44db68c5b7f5aa22b8fc7de74a3e2e08d1f29; version=7b71843fa7028475b052107664cbe120156a2cfc <b9bb9607b1fc12fca51f5632da25b36975f599bf; version=7b71843fa7028475b052107664cbe120156a2cfc <c1a5962f1462b64fe7b69f20a4b6af8067bc2d26; version=7b71843fa7028475b052107664cbe120156a2cfc <ce49569079a9d4cad26c0f1d4653382fd9a5ca7a; version=7b71843fa7028475b052107664cbe120156a2cfc <e6322fd177c6885a21dd4609dc5e5c973d1a2eb7; version=9871dea42034ee6e73bb2b97ba0284d3d462b230

Published CVSS scores

7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
CWE-667Improper Locking

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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