CVE-2025-68186

Published Dec 16, 2025 Modified Apr 15, 2026

Description

In the Linux kernel, the following vulnerability has been resolved: ring-buffer: Do not warn in ring_buffer_map_get_reader() when reader catches up The function ring_buffer_map_get_reader() is a bit more strict than the other get reader functions, and except for certain situations the rb_get_reader_page() should not return NULL. If it does, it triggers a warning. This warning was triggering but after looking at why, it was because another acceptable situation was happening and it wasn't checked for. If the reader catches up to the writer and there's still data to be read on the reader page, then the rb_get_reader_page() will return NULL as there's no new page to get. In this situation, the reader page should not be updated and no warning should trigger.

Is your site exposed to CVE-2025-68186?

Run a free security scan — no signup, results in seconds.

References

Frequently Asked Questions

What is CVE-2025-68186? +
In the Linux kernel, the following vulnerability has been resolved: ring-buffer: Do not warn in ring_buffer_map_get_reader() when reader catches up The function ring_buffer_map_get_reader() is a bit more strict than the other get reader functions, and except for certain situations the rb_get_reader_page() should not return NULL. If it does, it triggers a warning. This warning was triggering but after looking at why, it was because another acceptable situation was happening and it wasn't checked for. If the reader catches up to the writer and there's still data to be read on the reader page, then the rb_get_reader_page() will return NULL as there's no new page to get. In this situation, the reader page should not be updated and no warning should trigger.
How do I check if I'm vulnerable to CVE-2025-68186? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Don't wait for an exploit

Scan your website for vulnerabilities like CVE-2025-68186 — free, no signup required.