CVE-2026-98923 Linux CVE debrief

Who should care

Defenders and system administrators responsible for Linux kernel systems, especially those using versions 6.6.143, 6.12.93, 6.18.17, and 6.19.7 or earlier, should assess exposure and prioritize patching.

Why it matters

The Linux kernel vulnerability can cause a spurious WARN in ioremap_prot(). Defenders should prioritize verifying and applying patches for affected Linux kernel versions.

• Verify Linux kernel versions to determine exposure
• Apply patches to prevent spurious WARN in ioremap_prot()
• Monitor system logs for potential issues
• Ensure system updates are applied to prevent similar vulnerabilities

Technical summary

The Linux kernel vulnerability causes a spurious WARN in ioremap_prot() when mapping a stack-top page via /dev/mem with PROT_NONE and reading that process's /proc/<pid>/cmdline. This is due to ioremap_prot() receiving a protection value without PTE_USER. The vulnerability affects Linux kernel versions 6.6.143, 6.12.93, 6.18.17, and 6.19.7 or earlier. Defenders should prioritize verifying and applying patches for affected Linux kernel versions to prevent spurious WARN in ioremap_prot(). Ensure systems are updated to versions 6.6.158, 6.12.112, 6.18.55, or 7.0 and later.

Defensive priority

Defenders should prioritize verifying and applying patches for Linux kernel versions 6.6.143, 6.12.93, 6.18.17, and 6.19.7 or earlier. Ensure systems are updated to versions 6.6.158, 6.12.112, 6.18.55, or 7.0 and later.

Recommended defensive actions

• Verify Linux kernel versions and apply patches for 6.6.143, 6.12.93, 6.18.17, and 6.19.7 or earlier
• Update systems to Linux kernel versions 6.6.158, 6.12.112, 6.18.55, or 7.0 and later
• Monitor system logs for spurious WARN in ioremap_prot()
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and source item provide details on the Linux kernel vulnerability. The NVD entry is currently not provided. Evidence is limited to publicly available information from the CVE Program and source item. Defenders should verify the vulnerability's existence and impact through official sources and assess exposure based on their specific system configurations.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.