Skip to content
Fencer Vulns
high 7.5

CVE-2023-32256 json

Kernel: ksmbd race issue from smb2 close and logoff with multichannel

published 2025-08-01 15 mo ago modified 2026-11-06 2 d ago also EUVD-2023-36513

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 49%
public exploits
0
none known

Summary

A flaw was found in the Linux kernel's ksmbd component. A race condition between smb2 close operation and logoff in multichannel connections could result in a use-after-free issue.

Patch / fix

  • linux Debian 12 6.1.37-1
  • linux Debian 14, Debian 13 6.3.7-1

debian advisories DEBIAN-CVE-2023-32256

  • linux Ubuntu 22.04 LTS 5.15.0-102.112
  • linux-aws Ubuntu 22.04 LTS 5.15.0-1057.63
  • linux-gcp Ubuntu 22.04 LTS 5.15.0-1055.63
  • linux-gke Ubuntu 22.04 LTS 5.15.0-1054.59
  • linux-ibm Ubuntu 22.04 LTS 5.15.0-1050.53
  • linux-kvm Ubuntu 22.04 LTS 5.15.0-1054.59
  • linux-azure Ubuntu 22.04 LTS 5.15.0-1060.69
  • linux-gkeop Ubuntu 22.04 LTS 5.15.0-1040.46

ubuntu advisories UBUNTU-CVE-2023-32256

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2023-32256 updated cvss 7.5

kernel: ksmbd race issue from smb2 close and logoff with multichannel

  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more Red Hat Enterprise Linux 10 kernel
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
15 mo ago

Exploit prediction

0.61% chance of exploitation in the next 30 days, higher than 49% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:H

Affected products

  • Red Hat Red Hat Enterprise Linux 10
  • Red Hat Red Hat Enterprise Linux 6
  • Red Hat Red Hat Enterprise Linux 7
  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 9

Classification

Weakness
  • CWE-421 Race Condition During Access to Alternate Channel

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.