CVE-2026-89556module: validate string table section types

Official 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.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/50d0aa7d25ba4bc3606f150cd69755068e79f97f
• https://git.kernel.org/stable/c/e4496dda2c6d0acf7ba5fbce14a2723a8935ceee
• https://git.kernel.org/stable/c/9a5ff45689329835f874cefe5174e577d141d423