CVE-2019-1730 : What You Need to Know
Learn about CVE-2019-1730, a vulnerability in Cisco NX-OS Software allowing attackers to bypass restrictions and execute unauthorized commands. Find mitigation steps and long-term security practices here.
Cisco NX-OS Software Bash Bypass Guest Shell Vulnerability was published on May 15, 2019, with a CVSS base score of 6.0.
Understanding CVE-2019-1730
This CVE involves an authenticated, local attacker exploiting a vulnerability in Cisco NX-OS Software's Bash shell implementation.
What is CVE-2019-1730?
The vulnerability allows the attacker to bypass the restricted Guest Shell's command set and execute commands as a network-admin user outside of the Guest Shell.
The Impact of CVE-2019-1730
The vulnerability has a CVSS base score of 6.0 (Medium severity) with high availability and integrity impact.
Technical Details of CVE-2019-1730
The vulnerability is caused by an incorrectly implemented CLI command in Cisco NX-OS Software.
Vulnerability Description
An attacker with valid administrator credentials can execute commands outside the Guest Shell by crafting a specific command at the Guest Shell prompt.
Affected Systems and Versions
- Product: Cisco NX-OS Software
- Versions Affected: Less than 8.3(1)
Exploitation Mechanism
- Attacker needs to authenticate to the device
- Enter a crafted command at the Guest Shell prompt
- Successful exploit allows unauthorized commands.
Mitigation and Prevention
Immediate Steps to Take:
- Apply vendor patches promptly
- Monitor network for any unusual activity
- Restrict access to vulnerable systems
Long-Term Security Practices:
- Regularly update and patch systems
- Implement the principle of least privilege
- Conduct security awareness training for users
- Monitor vendor security advisories for updates and patches