CVE-2017-12340 : What You Need to Know
Learn about CVE-2017-12340, a vulnerability in Cisco NX-OS System Software allowing unauthorized access to Bash shell. Find mitigation steps and long-term security practices here.
A vulnerability in Cisco NX-OS System Software allows an attacker to access the Bash shell of affected devices, even if disabled.
Understanding CVE-2017-12340
This CVE involves a flaw in Cisco NX-OS System Software affecting Cisco Multilayer Director, Nexus 7000 Series, and Nexus 7700 Series Switches.
What is CVE-2017-12340?
The vulnerability enables a local attacker with authentication to access the Bash shell of the device's OS, bypassing disabled status.
The Impact of CVE-2017-12340
- Unauthorized access to Bash shell with user privileges
- Exploitation requires physical access and administrative or Python execution privileges
Technical Details of CVE-2017-12340
This section provides detailed technical insights into the CVE.
Vulnerability Description
The flaw arises from unsanitized user-supplied parameters in Python scripting sandbox functions, allowing an attacker to escape the sandbox.
Affected Systems and Versions
- Cisco Multilayer Director
- Nexus 7000 Series
- Nexus 7700 Series Switches
Exploitation Mechanism
- Attacker needs physical access and authentication
- Exploitation grants access to Bash shell with user privileges
Mitigation and Prevention
Protect your systems from CVE-2017-12340 with these mitigation strategies.
Immediate Steps to Take
- Apply vendor patches and updates promptly
- Restrict physical access to critical systems
- Monitor and log user activities for suspicious behavior
Long-Term Security Practices
- Implement least privilege access controls
- Regularly audit and update security configurations
Patching and Updates
- Stay informed about security advisories and patches
- Regularly update and patch affected systems