CVE-2019-1967 Cisco NX-OS Software Network Time Protocol Denial of Service Vulnerability
Remote attackers can cause denial of service on Cisco NX-OS devices by flooding them with Mode 7 NTP packets, leading to high resource usage and system reloads.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2019-1967?
CVE-2019-1967 is a high-severity denial of service vulnerability in Cisco Nx-Os, published on 29 Aug 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A vulnerability in the Network Time Protocol (NTP) feature of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to excessive use of system resources when the affected device is logging a drop action for received MODE_PRIVATE (Mode 7) NTP packets. An attacker could exploit this vulnerability by flooding the device with a steady stream of Mode 7 NTP packets. A successful exploit could allow the attacker to cause high CPU and memory usage on the affected device, which could cause internal system processes to restart or cause the affected device to unexpectedly reload. Note: The NTP feature is enabled by default.
Which versions are affected by CVE-2019-1967?
It affects 1 product.
Products include Cisco Nx-Os.
How do I fix CVE-2019-1967?
No fix has been published for CVE-2019-1967 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2019-1967 being exploited?
There is no known exploitation of CVE-2019-1967 in the wild and no public exploit code.
Other vulnerabilities in Cisco Nx-Os
Sources
Also known as GHSA-hvq8-fxqh-36fv.