CVE-2026-89499
CVE-2026-89499 is a security vulnerability. O3 Security confirms whether CVE-2026-89499 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: ring-buffer: Stop remote reader update when page swap fails The remote swap_reader_page callback can return -EBUSY…
Description
In the Linux kernel, the following vulnerability has been resolved:
ring-buffer: Stop remote reader update when page swap fails
The remote swap_reader_page callback can return -EBUSY when the writer moves the head before the remote catches it, particularly during an event storm on a small buffer. __rb_get_reader_page_from_remote() currently warns about that failure but continues with the unchanged reader ID and rearranges the local page list as though the swap succeeded.
Handle the callback failure as a recoverable error. Report it with pr_warn_ratelimited() and return NULL. Callers already handle a NULL reader page as a failed attempt. This avoids splicing the same page as both the previous and new reader without flooding the log under contention.
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-2026-89499 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-2026-89499 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-2026-89499. 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-2026-89499 in your dependencies?
O3 detects CVE-2026-89499 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.