CVE-2021-1243
5.3 · MEDIUMOverview
CVE-2021-1243 is a medium-severity vulnerability affecting cisco ios_xr. It was published on February 4, 2021 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
A vulnerability in the Local Packet Transport Services (LPTS) programming of the SNMP with the management plane protection feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to allow connections despite the management plane protection that is configured to deny access to the SNMP server of an affected device. This vulnerability is due to incorrect LPTS programming when using SNMP with management plane protection. An attacker could exploit this vulnerability by connecting to an affected device using SNMP. A successful exploit could allow the attacker to connect to the device on the configured SNMP ports. Valid credentials are required to execute any of the SNMP requests.
Remediation
Check the references section for vendor advisories and patches from cisco. Update ios_xr to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| cisco | ios_xr | >= 0, < 6.6.4 | Affected |
Frequently Asked Questions
What is CVE-2021-1243?
CVE-2021-1243 is a medium-severity vulnerability affecting cisco ios_xr. It was published on February 4, 2021 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
How severe is CVE-2021-1243?
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2021-1243?
Check the references section for vendor advisories and patches from cisco. Update ios_xr to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-1243?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-1243 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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