No. CVE-2026-53266
A Linux Kernel bug is being used in attacks
Yes. Attackers are using this right now.
What to do
Apply the vendor's update. If there is none, stop using it or cut it off from the internet.
- Confirmed in attacks
- Sep 18, 2026
- Product
- Linux Kernel
- Attack likelihood, next 30 days
- under 1%
Attack likelihood is EPSS, a daily estimate from FIRST.org of how likely this bug is to be used in attacks in the next 30 days.
The official description
Linux Kernel contains an out-of-bounds write vulnerability in the ebtables SNAT target which allows an ARP sender hardware address rewrite to write directly into a nonlinear socket-buffer fragment backed by a splice-imported file page. The impacted product(s) could be end-of-life (EoL) and/or end-of-service (EoS). Users are advised to discontinue use and/or transition to a supported version.
For your tech helper
A read-only checklist for whoever helps you with your computer, or an AI assistant. Paste it into Claude, ChatGPT or a coding agent; it only looks and changes nothing.
Read-only check, change nothing, send nothing anywhere.
Is Linux Kernel (CVE-2026-53266) installed or running on this machine or in this project?
1. Find every copy and its version (apps, packages, containers, lockfiles).
2. Compare each version against the vendor's fixed version for CVE-2026-53266. Quote the vendor page you used.
3. Report a table: where, version, fixed version, status (exposed / fixed / not installed / unsure).
4. List the exact update steps, but do not run them.