Reliance on Reverse DNS Resolution for a Security-Critical Action

Node.js before 10.24.0, 12.21.0, 14.16.0, and 15.10.0 is vulnerable to DNS rebinding attacks as the whitelist includes “localhost6”. When “localhost6” is not present in /etc/hosts, it is just an ordinary domain that is resolved via DNS, i.e., over network. If the attacker controls the victim's DNS server or can spoof its responses, the DNS rebinding protection can be bypassed by using the “localhost6” domain. As long as the attacker uses the “localhost6” domain, they can still apply the attack described in CVE-2018-7160.Show less

In Weave Net before version 2.6.3, an attacker able to run a process as root in a container is able to respond to DNS requests from the host and thereby insert themselves as a fake service. In a cluster with an IPv4 internal network, if IPv6 is not totally disabled on the host (via ipv6.disable=1 on the kernel cmdline), it will be either unconfigured or configured on some interfaces, but it's pretty likely that ipv6 forwarding is disabled, ie /proc/sys/net/ipv6/conf//forwarding == 0. Also by default, /proc/sys/net/ipv6/conf//accept_ra == 1. The combination of these 2 sysctls means that the host accepts router advertisements and configure the IPv6 stack using them. By sending rogue router advertisements, an attacker can reconfigure the host to redirect part or all of the IPv6 traffic of the host to the attacker controlled container. Even if there was no IPv6 traffic before, if the DNS returns A (IPv4) and AAAA (IPv6) records, many HTTP libraries will try to connect via IPv6 first then fallback to IPv4, giving an opportunity to the attacker to respond. If by chance you also have on the host a vulnerability like last year's RCE in apt (CVE-2019-3462), you can now escalate to the host. Weave Net version 2.6.3 disables the accept_ra option on the veth devices that it creates.Show less

The Node.js inspector, in 6.x and later is vulnerable to a DNS rebinding attack which could be exploited to perform remote code execution. An attack is possible from malicious websites open in a web browser on the same computer, or another computer with network access to the computer running the Node.js process. A malicious website could use a DNS rebinding attack to trick the web browser to bypass same-origin-policy checks and to allow HTTP connections to localhost or to hosts on the local network. If a Node.js process with the debug port active is running on localhost or on a host on the local network, the malicious website could connect to it as a debugger, and get full code execution access.Show less