Amped Wireless R10000 devices with firmware 2.5.2.11 use an improper algorithm for selecting the ID value in the header of a DNS query, which makes it easier for remote attackers to spoof responses by predicting this value.
Amped Wireless R10000 devices running firmware 2.5.2.11 are vulnerable to DNS spoofing attacks due to a flawed implementation of DNS query ID generation. This allows attackers to intercept and manipulate DNS responses, potentially redirecting users to malicious websites or enabling other network-based attacks, leading to compromise of network resources and user data theft.
Step 1: Target Identification: The attacker identifies an Amped Wireless R10000 device running firmware 2.5.2.11 on a network. Step 2: DNS Query Observation: The attacker monitors DNS queries originating from the target network, observing the source IP address of the router and the target domain being queried. Step 3: ID Prediction: The attacker analyzes the router's DNS query ID generation method (likely through observation and testing) to determine the predictability of the ID. Step 4: Crafting a Malicious Response: The attacker crafts a malicious DNS response with the predicted ID, spoofing the legitimate DNS server's response. The response contains the attacker's desired IP address for the target domain (e.g., a malicious IP). Step 5: Response Injection: The attacker sends the crafted malicious DNS response to the target network, attempting to deliver it before the legitimate response. Step 6: Cache Poisoning: If the attacker's response arrives first, the router caches the malicious DNS record. Step 7: Traffic Redirection: Subsequent DNS queries for the target domain from devices on the network will receive the attacker's IP address, redirecting traffic to the attacker's controlled server.
The vulnerability lies in the use of an improper algorithm for generating the DNS query ID. Instead of using a strong, unpredictable random number generator, the firmware likely employs a predictable or easily guessable method, such as incrementing a counter or using a weak pseudo-random number generator. This makes it significantly easier for an attacker to predict the ID used by the router when it sends a DNS query. By predicting the ID, an attacker can craft a malicious DNS response with the correct ID and send it before the legitimate response from the authoritative DNS server arrives. This allows the attacker to effectively poison the DNS cache of devices connected to the router, redirecting traffic to a malicious destination. The root cause is a lack of entropy and a reliance on a weak or predictable algorithm for ID generation, failing to adhere to secure coding practices for DNS implementations.