CVE-2021-1387

Cisco NX-OS Software IPv6 Netstack Denial of Service Vulnerability

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.

Category

8.6
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.38% Top 25%
Vendor Advisory cisco.com
Affected: Cisco Cisco NX-OS Software
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-1387?
CVE-2021-1387 has been scored as a high severity vulnerability.
How to fix CVE-2021-1387?
To fix CVE-2021-1387, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-1387 being actively exploited in the wild?
It is possible that CVE-2021-1387 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-1387?
CVE-2021-1387 affects Cisco Cisco NX-OS Software.
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