QID 316920

Date Published: 2021-04-15

QID 316920: Cisco IOS XE Software for Network Convergence System 520 Routers Denial of Service Vulnerability(cisco-sa-ncs520-tcp-ZpzzOxB)

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.

Affected Products
Cisco NCS 520 Routers if they were running a vulnerable release of Cisco IOS XE Software and had the HTTP server enabled.
Note: This vulnerability does not impact traffic that is going through the device or
going to the Management Ethernet interface of the device

QID Detection Logic (Authenticated):
The check matches Cisco IOS XE version retrieved via Unix Auth using "show version" command.
QID Detection Logic (Unauthenticated):
The check matches Cisco IOS XE version retrieved via SNMP or TCP/IP Fingerprint or NTP or Telnet.

A successful exploit could allow the attacker to cause the web management interface to become unavailable, resulting in a DoS condition.

  • CVSS V3 rated as Medium - 5.3 severity.
  • CVSS V2 rated as Medium - 4.3 severity.
    • Solution

    Customers are advised to refer to cisco-sa-ncs520-tcp-ZpzzOxB for more information.

    Vendor References

    CVEs related to QID 316920

    CVE-2021-1394 |
    Software Advisories
    Advisory ID Software Component Link
    cisco-sa-ncs520-tcp-ZpzzOxB URL Logo tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ncs520-tcp-ZpzzOxB
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