CVE-2026-76438 Overview
Cisco BroadWorks CommPilot Application Software contains an authorization bypass vulnerability in its web-based management interface. An authenticated remote attacker with low privileges can alter configurations on an affected device by sending a crafted HTTP request. The root cause is missing authorization checks on select pages of the management interface. The flaw is categorized under CWE-863: Incorrect Authorization.
Critical Impact
A low-privileged authenticated user can modify configuration settings that should be restricted to administrators, undermining the integrity of the BroadWorks CommPilot deployment.
Affected Products
- Cisco BroadWorks CommPilot Application Software (web-based management interface)
Discovery Timeline
- 2026-09-16 - CVE-2026-76438 published to the National Vulnerability Database (NVD)
- 2026-09-17 - Last updated in NVD database
Technical Details for CVE-2026-76438
Vulnerability Analysis
The vulnerability resides in the web-based management interface of Cisco BroadWorks CommPilot Application Software. Specific administrative pages fail to verify that the requesting user holds the privilege level required to modify configuration state. An attacker who already possesses valid low-privilege credentials can therefore invoke configuration-changing operations reserved for higher-privileged roles.
Successful exploitation compromises the integrity of the affected system by permitting unauthorized configuration changes on select pages. Confidentiality and availability are not directly affected according to the advisory metrics. Because the attack requires authenticated access, the exposure is scoped to users who already hold accounts on the BroadWorks platform, including compromised or malicious internal accounts.
Root Cause
The defect stems from missing authorization checks. Server-side handlers that process configuration modification requests do not enforce role-based access control before applying changes. Authentication alone is treated as sufficient to reach protected functionality, which is a classic broken access control pattern described by CWE-863.
Attack Vector
Exploitation is performed over the network against the CommPilot web interface. The attacker authenticates using low-privilege credentials, then issues a crafted HTTP request targeting a vulnerable configuration endpoint. The server processes the request without validating the caller's authorization, resulting in configuration changes. No user interaction is required and the attack complexity is low.
No public proof-of-concept or exploit code is currently listed for this issue. Refer to the Cisco Security Advisory on Auth Bypass for vendor technical details.
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Stop Identity AttacksDetection Methods for CVE-2026-76438
Indicators of Compromise
- Unexpected configuration changes on CommPilot pages that are typically reserved for administrator accounts.
- HTTP requests from low-privilege user sessions that reach configuration-modification endpoints.
- Audit log entries showing configuration writes correlated to accounts that historically only performed read operations.
Detection Strategies
- Enable and review CommPilot administrative audit logs for configuration changes attributed to non-administrative accounts.
- Baseline normal per-role HTTP request patterns and alert on deviations, especially POST or PUT requests to administrative paths from standard-user sessions.
- Correlate web server access logs with application-level authorization events to identify requests that succeeded despite insufficient privileges.
Monitoring Recommendations
- Forward BroadWorks CommPilot web interface and audit logs to a centralized SIEM for retention and correlation.
- Monitor for privilege-anomaly patterns where a user account performs actions outside its historical role scope.
- Alert on configuration drift by comparing periodic exports of CommPilot configuration state against a known-good baseline.
How to Mitigate CVE-2026-76438
Immediate Actions Required
- Apply the fixed release identified in the Cisco Security Advisory on Auth Bypass.
- Audit CommPilot user accounts and remove or downgrade any accounts that do not require access to the web management interface.
- Rotate credentials for low-privilege accounts that may have been exposed or shared.
- Review recent configuration changes for signs of unauthorized modification.
Patch Information
Cisco has published a security advisory tracking this issue. Consult the Cisco Security Advisory on Auth Bypass for the list of fixed software versions and upgrade guidance for Cisco BroadWorks CommPilot Application Software.
Workarounds
- Restrict network access to the CommPilot web-based management interface to trusted management networks using firewall or ACL controls.
- Enforce strong authentication and multi-factor authentication for all CommPilot accounts to reduce the risk of low-privilege account compromise.
- Continuously review role assignments and remove standing privileges that are not operationally required until the patch is applied.
# Example: restrict access to the CommPilot management interface to a trusted subnet
# (adapt interface names, addresses, and port to the local environment)
iptables -A INPUT -p tcp --dport 443 -s 10.10.20.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
