CVE-2026-72176

What the bug is

damon_sysfs_scheme_add_dirs() setup the tried_regions directory after the stats directory setup is completed. When the tried_regions directory setup is failed, the setup function ensures the reference for the tried regions directory is released. Hence the error path should put references on setup succeeded directory objects, starting from the stats directory. However, the error path is putting the tried_regions directory instead of the stats directory. As a direct result, the stats directory object is leaked. Worse yet, if the tried_regions directory setup failed from the initial allocation, the scheme->tried_regions field remains uninitialized. The following kobject_put(&scheme->tried_regions->kobj) call in the error path will dereference the uninitialized memory. The setup failures should not be common. But once it happens, the consequence is quite bad. Fix this issue by correctly putting the stats directory instead of the tried_regions directory. The issue was discovered [1] by Sashiko.

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.

mm/damon/sysfs-schemes.c

What this is

DAMONMAINTAINERS section matched on mm/damon/ · damon@lists.linux.dev · Maintained

Check it on the machine

grep -wE 'CONFIG_DAMON|CONFIG_DAMON_SYSFS' /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.

Show whether Debian builds this, per release

Debian builds this code. Every release with an answer below compiles the affected file into the kernels it ships. The build rule could not be established for 1 release, so nothing is claimed about those.

• bookworm?
• trixie, forky, sidy

?

not established - no Makefile entry for the affected file

y

built into the kernel image on every flavour - only a patch removes it

Where a release above reads "not established", no build rule for the affected file was found in that release's kernel tree. That is a gap in this lookup, not a finding that the code is absent.

Build switches

CONFIG_DAMON, CONFIG_DAMON_SYSFS

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

2026-08-15 (2 months ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.21%, higher than 10.3% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

unimportantsource

Subsystem

mm/damon

Upstream fixes

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

Introduced	Fixed in	Commit
6.2	6.6.145	50a753171d25
6.2	6.12.97	f63d6e5ba72a
6.2	6.18.40	40a04601a3f6
6.2	7.1.5	6b6b5d7c2c95
6.2	7.2	05ea83ee88ca