CVE-2026-87424 in Active Support Connectivity Gateway
Summary
by MITRE • 10/08/2026
A vulnerability in the SupportLink API authentication component of Brocade ASCG versions prior to 3.5.0 allows an attacker to bypass authentication across deployments due to the use of a hard coded cryptographic key.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 10/08/2026
The identified security flaw resides within the SupportLink Application Programming Interface (API) authentication mechanism found in Brocade Advanced Switching Control Group software, specifically affecting versions released prior to 3.5.0. This vulnerability stems from a critical implementation error where the system relies on a static, hard-coded cryptographic key for validating API requests across all deployments of the affected software version. In secure application design, authentication tokens or keys must be unique per deployment and generated using cryptographically strong random number generators to ensure unpredictability. By utilizing a single fixed key shared across multiple instances, the vendor inadvertently created a universal backdoor that compromises the integrity of the access control layer for every system running these vulnerable versions.
From a technical perspective, this flaw represents a classic instance of improper authentication due to the use of predictable or hard-coded secrets. The vulnerability allows an attacker who possesses knowledge of this static key to forge valid API requests without needing legitimate user credentials. Since the key is consistent across different deployments, compromising one system potentially provides the means to authenticate against others if they share the same configuration baseline or default settings. This undermines the fundamental principle of least privilege and ensures that any entity with network access to the affected interface can impersonate authorized administrators or services, effectively bypassing all intended security controls designed to restrict API usage.
The operational impact of this vulnerability is severe, as it grants unauthorized actors full control over the management plane of the Brocade ASCG infrastructure. An attacker could exploit this authentication bypass to execute arbitrary commands, modify network configurations, exfiltrate sensitive data, or pivot further into the internal network by leveraging the elevated privileges typically associated with API access in such environments. This level of compromise can lead to significant service disruptions, data breaches, and potential lateral movement within enterprise networks that rely on Brocade switching infrastructure for critical operations. The widespread nature of hard-coded keys means that a single exploit script could potentially target multiple vulnerable systems simultaneously if they are exposed to the same network segment or internet-facing interface.
This vulnerability aligns with Common Weakness Enumeration identifier CWE-798, which covers the use of hardcoded credentials, and is also associated with CWE-287 regarding improper authentication mechanisms. In terms of offensive security frameworks, this flaw facilitates initial access through exploitation of weak credential management practices, mapping to MITRE ATT&CK techniques related to valid accounts and unauthorized API usage. To mitigate this risk, organizations must immediately upgrade their Brocade ASCG software to version 3.5.0 or later, where the authentication mechanism has been corrected to use dynamic, unique keys per deployment. Additionally, administrators should audit network access controls to ensure that the SupportLink API interface is not exposed to untrusted networks and implement strict firewall rules limiting access to trusted management stations only until patches are applied.