CVE-2021-1387 Cisco NX-OS Software IPv6 Netstack Denial of Service Vulnerability
Unauthenticated remote attackers can cause a denial of service on Cisco NX-OS devices by sending crafted IPv6 packets that exhaust network stack buffers.
- 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-2021-1387?
CVE-2021-1387 is a high-severity denial of service vulnerability in Cisco Nx-Os, published on 24 Feb 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A vulnerability in the network stack of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability exists because the software improperly releases resources when it processes certain IPv6 packets that are destined to an affected device. An attacker could exploit this vulnerability by sending multiple crafted IPv6 packets to an affected device. A successful exploit could cause the network stack to run out of available buffers, impairing operations of control plane and management plane protocols and resulting in a DoS condition. Manual intervention would be required to restore normal operations on the affected device. For more information about the impact of this vulnerability, see the Details section of this advisory.
Weakness: CWE-401
Which versions are affected by CVE-2021-1387?
It affects 2 products.
Products include Cisco Nx-Os, Cisco Unified Computing System.
How do I fix CVE-2021-1387?
No fix has been published for CVE-2021-1387 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-2021-1387 being exploited?
There is no known exploitation of CVE-2021-1387 in the wild and no public exploit code.
Other vulnerabilities in Cisco Nx-Os
Sources
Also known as GHSA-78w3-6j2r-h8rq.