What happened
A Linux-based network toolkit known as DKnife has been observed hijacking router traffic to spy on users and deliver additional malware payloads. According to the report by Cisco Talos, security researchers have documented how DKnife targets Linux systems that serve as routers or network gateways, compromising them to insert malicious code that intercepts and redirects network traffic. Once installed, the toolkit enables the attacker to monitor traffic flows and deliver secondary payloads to connected devices via manipulated network streams. The malicious activity was identified through telemetry showing unauthorized firmware modifications and network behavior indicative of man-in-the-middle manipulation. DKnife’s capabilities include persistent network interception, credential harvesting, and remote installation of further malware, making it a potent threat to both home and small business networks that rely on Linux-based routing appliances.
Who is affected
Operators of Linux-based routers and network gateway systems are affected, as compromised devices can be used to intercept traffic and distribute malware to connected hosts.
Why CISOs should care
The DKnife toolkit represents a network-level threat where compromised infrastructure is abused to undermine trust in traffic flows, enabling credential theft and secondary payload delivery without direct interaction on client endpoints.
3 practical actions
- Scan for unauthorized firmware changes. Verify integrity of router and gateway system firmware against known good baselines.
- Monitor network traffic patterns. Look for redirects and anomalies consistent with interception or tampering.
- Isolate compromised infrastructure. Remove affected Linux gateway systems from production networks and remediate before reconnecting.