Banks, Shopify, Zoom Hit Again as Cloudflare's Second December Outage Reveals Your Internet's Fragility

A wave of 500 Internal Server Errors swept across the internet on 5 December 2025, knocking offline major banks, stock trading platforms, e-commerce giants, and video conferencing tools — marking Cloudflare's second significant outage within three weeks.

The San Francisco-based infrastructure provider, responsible for managing approximately 20% of global web traffic, confirmed that the incident began at 08:47 UTC and persisted for around 25 minutes before engineers rolled back a problematic configuration change. According to Cloudflare's own post-mortem report, the disruption impacted roughly 28% of all HTTP traffic routed through the company's network.

When the Shield Becomes the Weakness

The outage struck during peak business hours across Europe and early trading sessions in Asia, causing particular disruption to financial services. Bloomberg reported that websites for several banks went offline, along with those of Shopify, Zoom, and LinkedIn. In India, major stockbroking platforms—including Zerodha, Groww, Angel One, and Upstox—experienced outages during active trading hours, prompting some brokers to advise clients to use WhatsApp as an alternative for managing orders.

One user on X captured the chaos succinctly: 'My God — what a time for this massive outage. Banks, brokers... nothing is accessible. Frequent disruptions are affecting critical financial services. Internal Server Error 500 across multiple platforms.'

The technical cause was linked to an effort to safeguard users. Cloudflare had been rolling out updates to its Web Application Firewall to address CVE-2025-55182, an industry-wide vulnerability affecting React Server Components. When engineers disabled an internal testing tool that didn't support the new buffer size, a bug in Cloudflare's older FL1 proxy system triggered cascading failures across the network.

'Any outage of our systems is unacceptable, and we know we have let the internet down again following the incident on November 18,' Cloudflare acknowledged in its incident report.

A Pattern That Should Worry Everyone

This incident follows a far more severe outage on 18 November, when a Bot Management feature file, doubled in size due to a database permissions change, caused hours of disruption across services such as ChatGPT, X, Spotify, Canva, and many others. That event was described as Cloudflare's worst since 2019.

The rapid succession of outages has unsettled system administrators and business continuity planners alike. One Reddit user from the sysadmin community remarked: 'Cloudflare is down again. Two outages in two weeks. Anyone else concerned about the dependency chain here? It's not just websites that stop loading — it's SSO, API calls, AI platforms, monitoring dashboards, and even internal automations that have nothing to do with Cloudflare on paper.'

The real concern isn't merely theoretical. During both outages, affected organisations had no viable fallback options. They couldn't failover to backup infrastructure, reroute around the problem, or even diagnose the root cause beyond confirming Cloudflare was offline. Even Downdetector, a service designed to monitor outages, became inaccessible during the December incident.

The Uncomfortable Truth About Internet Centralisation

By acting as a buffer between websites and end users, Cloudflare's services protect against distributed denial-of-service (DDoS) attacks and enhance content delivery speeds. However, given its extensive use, when Cloudflare fails, the ripple effects are felt almost immediately and globally.

Richard Ford, chief technology officer at cybersecurity firm Integrity360, noted that such incidents are likely to become more frequent. 'We are seeing the frequency increase as organisations put more eggs in fewer baskets, and as the complexity and scale of operations like AWS, Google Cloud, Microsoft Azure, and Cloudflare grow,' he explained.

Reliance on a small number of dominant providers heightens the risk of single-point failures. The outages in November and December highlight growing concerns among experts about the systemic risks posed by internet centralisation.

Beyond the financial sector, the wider implications for operational continuity are profound. Critical services — including banking, e-commerce, government functions, and AI platforms — can be paralysed across continents by a single configuration error or technical glitch. The real question facing organisations today isn't whether the next outage will happen, but when and how severe its impacts might be.