data built 2026-10-19T13:16:53Z

Look up another CVE · open CVE-2026-93812 in the interactive tracker

CVE-2026-93812

ksmbd: fix sd_ndr.data memory leak in ksmbd_vfs_set_sd_xattr

EPSS 0.2%

Published 2026-09-24 (24 days ago) by the Linux kernel CNA. Subsystem fs/smb. Debian urgency: not yet assigned.

What to do, per Debian release

Debian's own status for CVE-2026-93812 in every release this site tracks, and what each one means in practice. Every status below is the one the Debian Security Team publishes for this CVE. source

ReleaseStatus VersionWhat this means
Debian 12bookwormfixedDLA-4841-1 · 2026-10-17 · text6.1.190-1Update the kernel and reboot. DLA-4841-1 shipped the fix on 2026-10-17, in 6.1.190-1. A running kernel keeps the old code until the machine restarts.
Debian 13trixiefixedDSA-6528-1 · 2026-09-29 · text6.12.111-1Update the kernel and reboot. DSA-6528-1 shipped the fix on 2026-09-29, in 6.12.111-1. A running kernel keeps the old code until the machine restarts.
Debian 14forkyfixed7.2.6-1Update the kernel and reboot. Fixed in 7.2.6-1. A running kernel keeps the old code until the machine restarts.
Debian unstablesidfixed7.2.6-1Update the kernel and reboot. Fixed in 7.2.6-1. A running kernel keeps the old code until the machine restarts.
Debian 12bookworm · linux-6.12fixedDLA-4817-1 · 2026-10-04 · text6.12.111-1~deb12u1Update the kernel and reboot. DLA-4817-1 shipped the fix on 2026-10-04, in 6.12.111-1~deb12u1. A running kernel keeps the old code until the machine restarts.

The vulnerability

What the bug is

ndr_encode_v4_ntacl() allocates sd_ndr.data via kzalloc() at entry. If any subsequent ndr_write_*() call returns error during encoding, the allocated sd_ndr.data won't be freed and causes memory leak. Move kfree(sd_ndr.data) into out label to ensure the buffer gets released on all success and error return paths.

Where it lives

The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.

fs/smb/server/vfs.c

What this is
KERNEL SMB3 SERVER (KSMBD)MAINTAINERS section matched on fs/smb/server/ · linux-cifs@vger.kernel.org · Maintained
Kernel module
ksmbd

Check it on the machine

grep -wE 'CONFIG_SMBFS|CONFIG_SMB_SERVER' /boot/config-$(uname -r)

Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.

lsmod | grep -w ksmbd

Prints a line if that module is loaded right now, and nothing if it is not. One that is not loaded can still be loaded later by anything that needs it.

Show whether Debian builds this, per release

Debian builds this as a loadable module. Every release below compiles it as a module on every flavour, so whether the code is in the running kernel depends on whether that module is loaded.

  • bookworm, trixie, forky, sid, bookworm · linux-6.12m
m
a loadable module on every flavour - check lsmod, can be blacklisted
Build switches
CONFIG_SMBFS, CONFIG_SMB_SERVER
Reads as
all on means the file is compiled; any one off means it is not.

From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages

Signals

Published
2026-09-24 (24 days ago)source
CVSS
no vector published, unrated
Attack vector
not published
EPSS
0.17%, higher than 6.2% of all CVEssource
CISA KEV
not listedthe KEV catalogue
Debian urgency
not yet assignedsource
Subsystem
fs/smb

Upstream fixes

The versions the CNA records as introducing and fixing this, and the commit for each. source

IntroducedFixed inCommit
5.155.15.222306d6f370da7
5.156.1.189dc55270e410c
5.156.6.158c866c3314a68
5.156.12.1119b4dec75498f
5.156.18.53c521dd78e036
5.157.2d4d56b00c7df

Debian advisories

AdvisoryDateShipped toDebian
DLA-4841-12026-10-17bookworm 6.1.190-1tracker
DLA-4817-12026-10-04bookworm 6.12.111-1~deb12u1tracker
DSA-6528-12026-09-29trixie 6.12.111-1tracker

Why the CNA scored it this way

The kernel CNA published no CVSS vector and no reasoning for CVE-2026-93812, which is why it is shown as unrated rather than given an invented score. 6,405 of the 20,413 CVEs here carry reasoning; this is not one of them.