1. Introduction
The remote host is running a Cisco Application Policy Infrastructure Controller Enterprise Module (APIC-EM) appliance. This vulnerability detects the presence of the APIC-EM web interface, which may allow an attacker to extract version and patch information if they have login credentials. Successful exploitation could lead to information disclosure impacting confidentiality. Keep this section under 120 words.
2. Technical Explanation
The vulnerability is the detection of a potentially exposed APIC-EM web interface. An attacker with network access and valid login credentials can use the web interface to gather detailed system information, including software versions and applied patches. This information could be used to identify known vulnerabilities and plan further attacks. There is no CVE associated with this specific detection; it’s an informational finding requiring investigation.
- Root cause: The APIC-EM web interface is accessible without proper access controls or monitoring.
- Exploit mechanism: An attacker logs into the APIC-EM web interface using valid credentials and navigates to pages containing system information.
- Scope: Cisco Application Policy Infrastructure Controller Enterprise Module (APIC-EM) appliances.
3. Detection and Assessment
Confirming whether a system is vulnerable involves checking for the presence of the APIC-EM web interface and assessing its accessibility.
- Quick checks: Use a web browser to access the appliance’s management IP address on port 443 (HTTPS). If a Cisco APIC-EM login page appears, the interface is present.
- Scanning: Nessus plugin ID 2791757d can detect this vulnerability. This should be used as an example only.
- Logs and evidence: Review web server logs for access attempts to the APIC-EM management IP address on port 443.
# Example command placeholder:
# No specific command available, use a web browser to check accessibility.
4. Solution / Remediation Steps
The following steps outline how to remediate the Cisco APIC-EM WebUI Detection vulnerability.
4.1 Preparation
- No services need to be stopped for this remediation.
- Roll back plan: Restore from the pre-change snapshot if issues occur. Change window approval may be required depending on your organisation’s policies.
4.2 Implementation
- Step 1: Review access control lists (ACLs) to ensure only authorized users can access the APIC-EM web interface.
- Step 2: Enable strong authentication methods, such as multi-factor authentication (MFA), for all APIC-EM accounts.
- Step 3: Regularly monitor logs for unauthorized access attempts to the APIC-EM web interface.
4.3 Config or Code Example
Before
# No specific configuration example available, as ACLs vary by environment.
# Assume default access allowing all internal IPs.
After
# Example ACL restricting access to a limited set of management IP addresses:
# Access-list 10 permit tcp any host eq https
# Access-list 10 deny ip any any
4.4 Security Practices Relevant to This Vulnerability
Several security practices can help prevent this vulnerability type.
- Practice 1: Least privilege – restrict access to sensitive systems and data based on the principle of least privilege.
- Practice 2: Strong authentication – enforce strong passwords, MFA, and regular password changes.
4.5 Automation (Optional)
No specific automation script is available for this vulnerability. However, infrastructure-as-code tools can be used to manage ACLs consistently across the environment.
# Example Ansible snippet:
# - name: Restrict access to APIC-EM web interface
# cisco.ios.ios_config:
# lines:
# - "access-list 10 permit tcp any host eq https"
# - "access-list 10 deny ip any any"
# parents: "interface Vlan1" # Replace with the relevant interface
5. Verification / Validation
Confirming the fix involves verifying that only authorized users can access the APIC-EM web interface and that unauthorized attempts are logged.
- Post-fix check: Attempt to access the APIC-EM web interface from an unauthorized IP address; access should be denied.
- Re-test: Re-run Nessus plugin ID 2791757d; it should no longer report the vulnerability if ACLs are correctly configured.
- Smoke test: Verify that authorized users can still log in and manage the APIC-EM appliance.
- Monitoring: Monitor web server logs for any unauthorized access attempts to port 443.
# Post-fix command and expected output:
# Attempting to access from an unapproved IP address should result in a connection refused or authentication error.
6. Preventive Measures and Monitoring
Update security baselines and implement monitoring for unauthorized access attempts. For example, regularly review ACLs and enable alerting on failed login attempts.
- Baselines: Update your security baseline to include restrictions on APIC-EM web interface access.
- Pipelines: Implement SAST or SCA tools to identify insecure configurations in infrastructure code.
- Asset and patch process: Review the configuration of all network devices regularly, including ACLs and authentication settings.
7. Risks, Side Effects, and Roll Back
Incorrectly configured ACLs may block legitimate access to the APIC-EM web interface.
- Roll back: Remove the added ACL lines from the configuration and restore the previous settings.
8. References and Resources
- Vendor advisory or bulletin: http://www.nessus.org/u?2791757d
- NVD or CVE entry: Not applicable, informational finding only.
- Product or platform documentation relevant to the fix: Cisco IOS Security Configuration Guide