CVE-2017-5243 : Security Advisory and Response

Rapid7 Nexpose hardware appliances shipped before June 2017 are vulnerable to various attacks due to a default SSH configuration issue.

Understanding CVE-2017-5243

The vulnerability in the SSH configuration of Rapid7 Nexpose hardware appliances exposes them to potential security risks.

What is CVE-2017-5243?

The pre-June 2017 Rapid7 Nexpose hardware appliances have a default SSH configuration that lacks specified preferred algorithms for key exchange and critical functions. This oversight allows all algorithms supported by the relevant version of OpenSSH, making the installations susceptible to MITM, downgrade, and decryption attacks.

The Impact of CVE-2017-5243

The vulnerability in CVE-2017-5243 can lead to unauthorized access, data interception, and potential compromise of sensitive information on affected systems.

Technical Details of CVE-2017-5243

Rapid7 Nexpose hardware appliances are affected by a cryptographic algorithm vulnerability in their SSH configuration.

Vulnerability Description

The default SSH configuration in Nexpose hardware appliances shipped before June 2017 does not specify desired algorithms for key exchange and other critical functions, leaving them open to various attacks.

Affected Systems and Versions

Product: Nexpose hardware appliance
Vendor: Rapid7
Versions: All Nexpose hardware appliances shipped before June 2017

Exploitation Mechanism

The vulnerability allows attackers to exploit the lack of specified algorithms in the SSH configuration to launch MITM, downgrade, and decryption attacks.

Mitigation and Prevention

Taking immediate steps and implementing long-term security practices are crucial to mitigating the risks associated with CVE-2017-5243.

Immediate Steps to Take

Update SSH configurations to specify preferred algorithms and disable obsolete ones.
Monitor network traffic for any suspicious activities.
Apply vendor-supplied patches or workarounds.

Long-Term Security Practices

Regularly update and patch all software and firmware on the affected appliances.
Implement network segmentation and access controls to limit exposure to potential attacks.

Patching and Updates

Rapid7 may release patches or updates to address the vulnerability in the affected Nexpose hardware appliances.