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Cloudflare mitigates 11.5 Tbps UDP flood DDoS attack

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📰 3 unique sources, 4 articles

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Cloudflare recently mitigated the largest recorded volumetric DDoS attack, peaking at 11.5 Tbps. The attack was a UDP flood primarily originating from a combination of several IoT and cloud providers, including Google Cloud. It lasted approximately 35 seconds. Cloudflare has seen a significant increase in DDoS attacks, with a 198% quarter-over-quarter increase and a 358% year-over-year jump in 2024. The company mitigated 21.3 million DDoS attacks targeting its customers and 6.6 million attacks targeting its own infrastructure during an 18-day multi-vector campaign in 2024. The most significant spike was seen by network-layer attacks, which saw a 509% year-over-year increase since the start of 2025. The attack was part of a series of hyper-volumetric DDoS attacks, with the largest reaching peaks of 5.1 Bpps and 11.5 Tbps. The attack was conducted by sending requests from botnets that had infected devices with malware. The RapperBot kill chain targets network video recorders (NVRs) and other IoT devices for DDoS attacks. The malware exploits security flaws in NVRs to gain initial access and download the payload, using a path traversal flaw to leak valid administrator credentials and push a fake firmware update. The malware establishes an encrypted connection to a C2 domain to receive commands for launching DDoS attacks and can scan the internet for open ports to propagate the infection. The attackers' methodology involves scanning the internet for old edge devices and brute-forcing or exploiting them to execute the botnet malware. Google's abuse defenses detected the attack, and they followed proper protocol in customer notification and response. Cloudflare has been automatically mitigating hundreds of hyper-volumetric DDoS attacks in recent weeks, with the largest reaching peaks of 5.1 Bpps and 11.5 Tbps. Volumetric attacks typically aim to overwhelm servers or networks, causing them to slow or shut down completely. The attack's short duration of 35 seconds highlights that size alone is not the most critical metric for evaluating DDoS attacks. The complexity and persistence of an attack, along with its impact on users, are more important metrics for DDoS defense. A DDoS mitigation service provider in Europe was targeted in a 1.5 Bpps denial-of-service attack. The attack originated from thousands of IoTs and MikroTik routers and was mitigated by FastNetMon. The attack was primarily a UDP flood launched from compromised customer-premises equipment (CPE), including IoT devices and routers, across more than 11,000 unique networks worldwide. The attack was detected in real-time, and mitigation action was taken using the customer's DDoS scrubbing facility. FastNetMon's founder, Pavel Odintsov, called for ISP-level intervention to stop the weaponization of compromised consumer hardware. The attack was one of the largest packet-rate floods publicly disclosed.

Timeline

  1. 11.09.2025 01:09 📰 1 articles

    FastNetMon mitigates 1.5 Bpps UDP flood DDoS attack

    A DDoS mitigation service provider in Europe was targeted in a 1.5 Bpps denial-of-service attack. The attack originated from thousands of IoTs and MikroTik routers and was mitigated by FastNetMon. The attack was primarily a UDP flood launched from compromised customer-premises equipment (CPE), including IoT devices and routers, across more than 11,000 unique networks worldwide. The attack was detected in real-time, and mitigation action was taken using the customer's DDoS scrubbing facility. FastNetMon's founder, Pavel Odintsov, called for ISP-level intervention to stop the weaponization of compromised consumer hardware. The attack was one of the largest packet-rate floods publicly disclosed. This attack highlights the ongoing trend of hyper-volumetric DDoS attacks and the need for proactive measures at the ISP level to mitigate such threats.

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  2. 02.09.2025 18:52 📰 3 articles

    Cloudflare mitigates 11.5 Tbps UDP flood DDoS attack

    Cloudflare recently mitigated the largest recorded volumetric DDoS attack, peaking at 11.5 Tbps. The attack was a UDP flood primarily originating from a combination of several IoT and cloud providers, including Google Cloud. It lasted approximately 35 seconds. This follows a significant increase in DDoS attacks, with a 198% quarter-over-quarter increase and a 358% year-over-year jump in 2024. Cloudflare mitigated 21.3 million DDoS attacks targeting its customers and 6.6 million attacks targeting its own infrastructure during an 18-day multi-vector campaign in 2024. The most significant spike was seen by network-layer attacks, which saw a 509% year-over-year increase since the start of 2025. The attack was part of a series of hyper-volumetric DDoS attacks, with the largest reaching peaks of 5.1 Bpps and 11.5 Tbps. The attack was conducted by sending requests from botnets that had infected devices with malware. The RapperBot kill chain targets network video recorders (NVRs) and other IoT devices for DDoS attacks. The malware exploits security flaws in NVRs to gain initial access and download the payload, using a path traversal flaw to leak valid administrator credentials and push a fake firmware update. The malware establishes an encrypted connection to a C2 domain to receive commands for launching DDoS attacks and can scan the internet for open ports to propagate the infection. The attackers' methodology involves scanning the internet for old edge devices and brute-forcing or exploiting them to execute the botnet malware. Google's abuse defenses detected the attack, and they followed proper protocol in customer notification and response. Cloudflare has been automatically mitigating hundreds of hyper-volumetric DDoS attacks in recent weeks, with the largest reaching peaks of 5.1 Bpps and 11.5 Tbps. Volumetric attacks typically aim to overwhelm servers or networks, causing them to slow or shut down completely. The attack's short duration of 35 seconds highlights that size alone is not the most critical metric for evaluating DDoS attacks. The complexity and persistence of an attack, along with its impact on users, are more important metrics for DDoS defense. Cloudflare intends to release a detailed report on the attack soon.

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