CVE Catalog

CVE-2026-74600

Low risk· EPSS 10%
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.20%

10th percentile - higher than 10% of all known CVEs

Summary

In the Linux kernel, the page_table_check mechanism incorrectly accounts special zero mappings (shared zero-page and huge zero PMD) as file-backed pages. An unprivileged process can create enough such mappings to overflow file_map_count and trigger BUG_ON().

Risk Assessment

An unprivileged attacker can cause a kernel panic, leading to system downtime.

Recommendation

Apply the kernel update that skips special zero mappings in user page-table accounting paths.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: mm/page_table_check: skip special zero mappings page_table_check_set() and page_table_check_clear() account mappings based on PageAnon(). Shared zero-page PTEs and huge zero PMDs are special mappings, but page_table_check can still account them as file-backed pages. An unprivileged process can populate enough zero mappings to overflow file_map_count and hit the existing BUG_ON(). The PTE path can do this with the shared zero page, and the PMD path can do the same with huge zero mappings. Skip special zero mappings in the user page-table accounting paths. Keep the PTE-side pte_special() check, and identify huge zero PMDs from the mapped folio instead of pmd_special(). That covers architectures where pmd_special() is a no-op without adding huge_zero_pfn checks to the generic counter helpers.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS