Original article ISPreview UK:Read More
Customers connected to UK ISP Youfibre (and possibly other ISPs) on one of the country’s largest alternative full fibre (FTTP) broadband networks, Netomnia (Substantial Group), are currently understood to be experiencing “intermittent connectivity or slower-than-usual performance” due to an ongoing Distributed Denial of Service (DDoS) attack.
DDoS attacks work by attempting to overload target servers or end-user with masses of data requests from multiple internet connected devices (often malware hijacked computers / botnets etc.), which can cause the intended target to crash or suffer performance problems until the bad traffic stops or can be mitigated. On rare occasions, such attacks may also expose other weaknesses to exploit, such as happened with TalkTalk in 2015 (here).
Sadly, it’s not uncommon for UK broadband providers and networks to be hit by DDoS attacks, which happen all the time. But most of those can be mitigated and only very few are usually big enough to actually be noticed by customers. Sometimes such incidents may not even be an attack against the network operator, but rather somebody targeting a specific customer or upstream network provider for the ISP etc.
Most internet providers usually prefer not to speak about such things in public, often putting related incidents down to ambiguous network connectivity faults instead. But some are more open and honest than others. In this case, Youfibre’s CEO, Jeremy Chelot, has confirmed (X) that a DDoS is ongoing: “Please bear with us. We are under attack.”
Youfibre Service Statement
We are currently experiencing an unexpected issue affecting parts of our network, which may result in intermittent connectivity or slower-than-usual performance. Our network engineers are investigating the source of the disruption and are taking immediate steps to mitigate the impact and restore full service.
UPDATE 11:46am
Customers are reporting a return to normal service and the ISP has provided the following update: “We can confirm that the issues have been fully resolved. We appreciate your understanding and patience during this time.”
UPDATE 3:40pm
Clearly the attackers have adapted their methods or started a new assault (not uncommon with DDoS). We’ve seen customer reports of more problems, and YouFibre just issued the following update (X): “We are sorry to report that YouFibre has been subjected to a DDoS attack today (28.11.25). We are working very hard to resolve this. From a high level, a DDoS attack is a malicious attack that creates a flood of internet traffic affecting service performance. Please keep an eye out for updates in your inbox and on our network updates page here on X – @youfibre_status . We hope normal service will return quickly.”
UPDATE 29th Nov 2025 @ 7:30am
Youfibre has yet to issue a further service status update, but the provider does appear to have had some success in mitigating the attack. Separately, ISPreview has noted that Cogent reported a DDoS taking place yesterday afternoon against one of their customers in Equinix’s MA1 Manchester Data Centre, which could have impacted those with Cogent transit in MA1 (e.g. Youfibre).
We have also seen reports of several other – larger – ISPs being hit by a big DDoS yesterday (e.g. BT), although if so they were quick to mitigate it on the first pass (scale helps) and most customers won’t have noticed, while those that did only saw a fairly brief period of disruption.