CVE-2016-6301: High severity advantech spectre rt ert351 firmware vulnerability
The busybox NTP implementation doesn't check the NTP mode of packets received on the server port and responds to any packet with the right size. This includes responses from another NTP server. An attacker can send a packet with a spoofed source address in order to create an infinite loop of responses between two busybox NTP servers. Adding more packets to the loop increases the traffic between the servers until one of them has a fully loaded CPU and/or network.
It seems this bug was actually inherited from openntpd, on which the busybox implementation was based on. In openntpd it was fixed in:
https://github.com/openntpd-portable/openntpd-openbsd/commit/28a2f904aafbf4c209fe6fa04ffb9308740fd78a
Busybox upstream patch:
https://git.busybox.net/busybox/commit/?id=150dc7a2b483b8338a3e185c478b4b23ee884e71
Other sources
The recvandprocessclientpkt function in networking/ntpd.c in busybox allows remote attackers to cause a denial of service (CPU and bandwidth consumption) via a forged NTP packet, which triggers a communication loop.
— MITRE
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2016-6301?
CVE-2016-6301 is classified as a high-severity vulnerability due to its potential for creating denial-of-service conditions.
How do I fix CVE-2016-6301?
To fix CVE-2016-6301, upgrade to BusyBox version 1.25.1 or later, or apply patches from your vendor.
What kind of systems are affected by CVE-2016-6301?
CVE-2016-6301 affects BusyBox implementations as well as Advantech Spectre RT ERT351 firmware Versions 5.1.3 and prior.
What type of attack is associated with CVE-2016-6301?
CVE-2016-6301 is associated with NTP reflection attacks where an attacker can spoof source addresses to create an amplification effect.
Is CVE-2016-6301 still a concern in current systems?
Yes, CVE-2016-6301 remains a concern if systems using vulnerable versions of BusyBox or Advantech firmware are not updated.