CVE-2021-1394

Cisco IOS XE Software for Network Convergence System 520 Routers Denial of Service Vulnerability

Description

A vulnerability in the ingress traffic manager of Cisco IOS XE Software for Cisco Network Convergence System (NCS) 520 Routers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition in the web management interface of an affected device. This vulnerability is due to incorrect processing of certain IPv4 TCP traffic that is destined to an affected device. An attacker could exploit this vulnerability by sending a large number of crafted TCP packets to the affected device. A successful exploit could allow the attacker to cause the web management interface to become unavailable, resulting in a DoS condition. Note: This vulnerability does not impact traffic that is going through the device or going to the Management Ethernet interface of the device.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.07%
Vendor Advisory cisco.com
Affected: Cisco Cisco IOS XE Software
Published at:
Updated at:

References

Link Tags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ncs520-tcp-ZpzzOxB vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-1394?
CVE-2021-1394 has been scored as a medium severity vulnerability.
How to fix CVE-2021-1394?
To fix CVE-2021-1394, 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-2021-1394 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-1394 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-1394?
CVE-2021-1394 affects Cisco Cisco IOS XE Software.
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