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

Look up another CVE · open CVE-2026-74399 in the interactive tracker

CVE-2026-74399

evm: terminate and bound the evm_xattrs read buffer

EPSS 0.2%

Published 2026-08-15 (2 months ago) by the Linux kernel CNA. Subsystem security/integrity. Debian urgency: not yet assigned.

What to do, per Debian release

Debian's own status for CVE-2026-74399 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 12bookwormfixed6.1.180-1Update the kernel and reboot. Fixed in 6.1.180-1. A running kernel keeps the old code until the machine restarts.
Debian 13trixiefixed6.12.100-1Update the kernel and reboot. Fixed in 6.12.100-1. A running kernel keeps the old code until the machine restarts.
Debian 14forkyfixed7.1.5-1Update the kernel and reboot. Fixed in 7.1.5-1. A running kernel keeps the old code until the machine restarts.
Debian unstablesidfixed7.1.5-1Update the kernel and reboot. Fixed in 7.1.5-1. A running kernel keeps the old code until the machine restarts.

The vulnerability

What the bug is

evm_read_xattrs() allocates size + 1 bytes, fills them from the list of enabled xattrs, and then passes strlen(temp) to simple_read_from_buffer(). When no configured xattrs are enabled, the fill loop stores nothing and temp[0] remains uninitialized, so strlen() reads beyond initialized memory. Explicitly terminate the buffer after allocation, use snprintf() for each formatted line, and pass the accumulated length, without risk of truncation, to simple_read_from_buffer().

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.

security/integrity/evm/evm_secfs.c

What this is
Extended Verification Module (EVM)MAINTAINERS section matched on security/integrity/evm/ · linux-integrity@vger.kernel.org · Supported

Check it on the machine

grep -wE 'CONFIG_EVM|CONFIG_INTEGRITY' /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 below compiles the affected file into the kernels it ships.

  • bookworm, trixie, forky, sidy
y
built into the kernel image on every flavour - only a patch removes it
Build switches
CONFIG_EVM, CONFIG_INTEGRITY
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 11.0% of all CVEssource
CISA KEV
not listedthe KEV catalogue
Debian urgency
not yet assignedsource
Subsystem
security/integrity

Upstream fixes

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

IntroducedFixed inCommit
4.185.15.2128df81954d22a
4.186.1.1780b9f8282b40a
4.186.6.145a36cbfb85f26
4.186.12.9712ad52dc45a0
4.186.18.40a0f64cf8bfcb
4.187.1.538b7d63b23aa
4.187.211143a19f5b8

Why the CNA scored it this way

The kernel CNA published no CVSS vector and no reasoning for CVE-2026-74399, 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.