On 29 April, a newly-discovered Linux vulnerability was announced. Known as Copy Fail and categorised as CVE-2026-31431, this vulnerability had been introduced in 2017 and affected every Linux distribution. It allowed “unprivileged local users [to] write 4 controlled bytes into the page cache of any readable file on a Linux system, and use that to gain root access”.
In plain language, Copy Fail is an easily exploitable vulnerability that enables root access to attackers. Consequently, it received the highest possible severity rating.
Within a day of the CVE being published, we had patched the entire Webslice Containers fleet. Our customers didn’t need to lift a finger, didn’t need to report anything, and in a lot of cases might not even have known that there was anything to worry about. It’s our job to do the worrying—and the fixing—for you.
Vulnerability reports like this are multiplying
Copy Fail could easily be one of 60,000 common vulnerabilities and exposures (CVEs) reported this year. Ten years ago, the number was under 7,000. From 2024 to 2025, the annual total jumped 20% to 48,185. The age of AI has changed web security, making it quicker and easier to find and report vulnerabilities. Of course, it also makes it easier to exploit them.
The job of keeping up with disclosures, prioritizing responses and maintaining secure systems is getting more complicated. Old patching routines are no longer adequate, and more attention is required.
If web security isn’t an area of expertise for you, we recommend having a team on your side.
Get even more with Support & Management
Because Copy Fail affected Linux, it was something that we quickly patched on every Webslice Containers server. By adding Support & Management, you can put our team at your service in even more situations, all the way from Linux up to the apps running in your containers.
Support & Management is an easy way for you to spend even less time worrying about infrastructure or responding to issues. Read all about it in the Webslice Containers documentation.