CVE-2021-1394 Cisco IOS XE Software for Network Convergence System 520 Routers Denial of Service Vulnerability
Remote attackers can cause a denial of service in the web management interface of Cisco NCS 520 Routers by sending crafted TCP packets.
- 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-2021-1394?
CVE-2021-1394 is a medium-severity denial of service vulnerability in Cisco Ios Xe, published on 24 Mar 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-399
Which versions are affected by CVE-2021-1394?
It affects 1 product.
Products include Cisco Ios Xe.
How do I fix CVE-2021-1394?
No fix has been published for CVE-2021-1394 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-2021-1394 being exploited?
There is no known exploitation of CVE-2021-1394 in the wild and no public exploit code.
Other vulnerabilities in Cisco Ios Xe
- CVE-2023-20198 Cisco IOS XE Web UI Privilege Escalation
- CVE-2018-0151 Cisco IOS Software and Cisco IOS XE Software Quality of Service Remote Code Execution
- CVE-2023-20273 Cisco IOS XE Web UI Command Injection
- CVE-2025-20188 Hardcoded credentials in Cisco IOS XE Software
- CVE-2021-34770 Cisco IOS XE Software for Catalyst 9000 Family Wireless Controllers CAPWAP Remote Code Execution Vulnerability
Sources
Also known as GHSA-x482-c63f-45hq.