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

Look up another CVE · open CVE-2026-89556 in the interactive tracker

CVE-2026-89556

module: validate string table section types

EPSS 0.2%

Published 2026-09-11 (37 days ago) by the Linux kernel CNA. Subsystem kernel/module. Debian urgency: unimportant.

What to do, per Debian release

Debian's own status for CVE-2026-89556 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 12bookwormnot affected6.1.190-1Nothing to do. bookworm never shipped the vulnerable code.
Debian 13trixienot affected6.12.113-1Nothing to do. trixie never shipped the vulnerable code.
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.

The vulnerability

What the bug is

In elf_validity_cache_sechdrs, section sizes and offsets are validated, unless the section type is SHT_NULL or SHT_NOBITS. Later, elf_validity_cache_secstrings and elf_validity_cache_index_str access the section name table (.shstrtab) and symbol string table (.strtab) headers without first ensuring that their types are SHT_STRTAB. If a section type is SHT_NULL or SHT_NOBITS, sh_offset has not been validated and may reference out-of-bounds memory when dereferenced in elf_validity_cache_secstrings or elf_validity_cache_strtab. Validate that both string section headers are of type SHT_STRTAB before caching them.

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.

kernel/module/main.c

What this is
MODULE SUPPORTMAINTAINERS section matched on kernel/module/ · linux-modules@vger.kernel.org · Maintained

Check it on the machine

grep -w CONFIG_MODULES /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 switch
CONFIG_MODULES

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
2026-09-11 (37 days ago)source
CVSS
no vector published, unrated
Attack vector
not published
EPSS
0.20%, higher than 8.9% of all CVEssource
CISA KEV
not listedthe KEV catalogue
Debian urgency
unimportantsource
Subsystem
kernel/module

Upstream fixes

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

IntroducedFixed inCommit
6.136.18.5050d0aa7d25ba
6.137.2.4e4496dda2c6d
6.137.39a5ff4568932

Why the CNA scored it this way

The kernel CNA published no CVSS vector and no reasoning for CVE-2026-89556, 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.