CVE-2026-89967
CVE-2026-89967 is a security vulnerability. O3 Security confirms whether CVE-2026-89967 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
In the Linux kernel, the following vulnerability has been resolved: mm/migrate_device: avoid out-of-bounds writes for compound folios migrate_device_range() and migrate_device_pfns()…
Description
In the Linux kernel, the following vulnerability has been resolved:
mm/migrate_device: avoid out-of-bounds writes for compound folios
migrate_device_range() and migrate_device_pfns() clear the entries following a compound folio so that the PFN arrays retain their page-granular representation.
If a compound folio extends beyond the end of the caller-provided range, the loops clear all following folio entries without limiting them to the number of slots remaining in the npages-sized array, causing an out-of-bounds write.
Do not proceed with a compound folio if its page-granular representation does not fit entirely in the remaining PFN array. If this happens, drop any reference and lock acquired for the folio, clear the remaining entries, and stop collecting.
Observed with a KASAN x86 QEMU kernel using the HMM migrate_anon_huge_zero selftest. Closing /dev/hmm_dmirror0 after migrating an anonymous huge page to device memory exercises:
dmirror_fops_release() -> dmirror_device_evict_chunk() -> migrate_device_range()
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2026-89967 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-89967 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-89967. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-89967 in your dependencies?
O3 detects CVE-2026-89967 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.