CVE-2017-12236 Explained : Impact and Mitigation

Cisco IOS XE software versions 3.2 through 16.5 are affected by a vulnerability in the Locator/ID Separation Protocol (LISP) implementation. Unauthorized users could exploit this flaw to bypass authentication checks, potentially injecting incorrect mappings in the map server/map resolver (MS/MR).

Understanding CVE-2017-12236

This CVE entry highlights a critical vulnerability in Cisco IOS XE software versions 3.2 through 16.5 related to the implementation of the Locator/ID Separation Protocol (LISP).

What is CVE-2017-12236?

The vulnerability allows unauthorized individuals with access to an x tunnel router to bypass authentication checks when registering an Endpoint Identifier (EID) to a Routing Locator (RLOC) in the map server/map resolver (MS/MR) of affected Cisco devices configured with LISP acting as an IPv4 or IPv6 map server.

The Impact of CVE-2017-12236

Exploitation of this flaw could lead to the injection of incorrect mappings of EIDs to RLOCs in the MS/MR of the affected software, compromising the integrity and security of the network infrastructure.

Technical Details of CVE-2017-12236

This section delves into the technical aspects of the vulnerability.

Vulnerability Description

The flaw in the LISP implementation in Cisco IOS XE software versions 3.2 through 16.5 allows attackers to send specific map-registration requests to the affected software, bypassing authentication checks and injecting invalid mappings of EIDs to RLOCs in the MS/MR.

Affected Systems and Versions

Cisco IOS XE software versions 3.2 through 16.5
Specifically impacts Cisco IOS XE Software release trains 3.9E and Everest 16.4

Exploitation Mechanism

Unauthorized users with access to an x tunnel router can exploit the flaw to bypass authentication checks
Attackers can send specific valid map-registration requests to the affected software, even if authentication keys do not match

Mitigation and Prevention

To address CVE-2017-12236, follow these mitigation strategies:

Immediate Steps to Take

Apply the necessary patches provided by Cisco to fix the vulnerability
Monitor network traffic for any suspicious activities

Long-Term Security Practices

Regularly update and patch all software and firmware to prevent future vulnerabilities
Implement strong access controls and authentication mechanisms

Patching and Updates

Cisco has released patches to address the vulnerability
Ensure all affected systems are updated with the latest software versions and security patches