CVE-2026-89556

Received Received - Intake

Memory Corruption in Linux Kernel Module

Publication date: 2026-09-11

Last updated on: 2026-09-13

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: module: validate string table section types 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.

CVSS Scores

EPSS Scores

Probability:
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Meta Information

Published

2026-09-11

Last Modified

2026-09-13

Generated

2026-10-02

AI Q&A

2026-09-12

EPSS Evaluated

2026-09-29

NVD

CVE-2026-89556

EUVD

EUVD-2026-76467

Affected Vendors & Products

Vendor	Product	Version / Range
linux	linux_kernel	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This vulnerability in the Linux kernel involves improper validation of ELF section headers. The issue occurs when section sizes and offsets are not checked for certain section types, allowing out-of-bounds memory access. Specifically, the string table section headers (.shstrtab and .strtab) are accessed without verifying they are of the correct type (SHT_STRTAB), which could lead to memory corruption or crashes.

Detection Guidance

This vulnerability is specific to the Linux kernel and requires examining kernel module loading behavior. Check kernel logs for module loading errors or crashes using 'dmesg | grep -i module' or 'journalctl -k | grep -i module'. Inspect loaded modules with 'lsmod' and verify kernel version with 'uname -a'.

Impact Analysis

This vulnerability could allow an attacker to cause a denial of service (system crash) or potentially execute arbitrary code with kernel privileges. It may also lead to memory corruption, compromising system stability and security. Users running affected Linux kernel versions are at risk if the flaw is exploited.

Compliance Impact

This vulnerability could impact compliance by exposing systems to unauthorized access or data breaches, violating confidentiality requirements in GDPR or HIPAA. Organizations must patch affected systems to maintain compliance with security and privacy standards.

Mitigation Strategies

Apply the latest kernel security patches from your Linux distribution. Avoid loading untrusted kernel modules. Monitor system stability and kernel logs for unusual activity. Consider disabling module loading if not required using 'echo 0 > /proc/sys/kernel/modules_disabled'.

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