Some people may have witnessed ’empty pages’ on some websites in early December.

The problem hit websites run by Cloudflare, including big names such as LinkedIn and Canva.

DownDetector, a site used to monitor online service issues, also went down as a result of the issue. When it came back online, it recorded more than 4,500 reports related to issues at Cloudflare, according to Sky News.

Cloudflare, which provides network and security services for many online businesses, claims that around a fifth of all websites use some form of its services.

This follows a wider incident in November affecting companies such as bet365, alongside Facebook, X, Spotify, and Amazon Web Services.

In the latest incident, Cloudflare said it quickly implemented a fix.

Experts say the outage came as Cloudflare acted to mitigate a  a maximum severity vulnerability in React2Shell. Cloudflare forced a widespread outage , causing websites and online platforms worldwide to go down and sending back a “500 Internal Server Error” message. 

It is believed that state sponsored Chinese cyber threat actors may be exploiting vulnerabilities,

In its blog, Cloudflare wrote:

On December 5, 2025, at 08:47 UTC (all times in this blog are UTC), a portion of Cloudflare’s network began experiencing significant failures. The incident was resolved at 09:12 (~25 minutes total impact), when all services were fully restored.

A subset of customers were impacted, accounting for approximately 28% of all HTTP traffic served by Cloudflare. Several factors needed to combine for an individual customer to be affected as described below.

The issue was not caused, directly or indirectly, by a cyber attack on Cloudflare’s systems or malicious activity of any kind. Instead, it was triggered by changes being made to our body parsing logic while attempting to detect and mitigate an industry-wide vulnerability n React Server Components.