CVE-2021-1243

Cisco IOS XR Software SNMP Management Plane Protection ACL Bypass Vulnerability

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.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.68% Top 30%
Vendor Advisory cisco.com
Affected: Cisco Cisco IOS XR Software
Published at:
Updated at:

References

Link Tags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snmp-7MKrW7Nq vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-1243?
CVE-2021-1243 has been scored as a medium severity vulnerability.
How to fix CVE-2021-1243?
To fix CVE-2021-1243, 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-2021-1243 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-1243 is being actively exploited. 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-2021-1243?
CVE-2021-1243 affects Cisco Cisco IOS XR Software.
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