CVE-2026-73741 in Fabric Composer
Summary
by MITRE • 09/01/2026
A vulnerability in the API of HPE Networking Fabric Composer could allow an authenticated low privilege operator user to view some system files. Successful exploitation could allow an attacker to access limited data beyond what is authorized by the user's existing privilege level.
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Analysis
by VulDB Data Team • 09/02/2026
The identified security flaw resides within the application programming interface (API) of Hewlett Packard Enterprise Networking Fabric Composer, a centralized management platform used for orchestrating and managing network infrastructure components such as switches and routers. This vulnerability specifically affects users who have been assigned low-privilege operator roles, which are typically intended to restrict access to only essential monitoring and basic configuration functions. The core technical deficiency is an improper authorization check within the API endpoints that handle file system operations or data retrieval requests. Instead of strictly validating whether the requesting user has explicit permission to access specific sensitive system files based on their role-based access control policies, the application fails to enforce these boundaries effectively. This logic error allows a malicious actor who possesses valid credentials for an operator account to craft specific API calls that bypass intended restrictions and retrieve contents from restricted areas of the underlying operating system or configuration databases.
From a technical perspective, this issue represents a classic case of broken access control where the application does not sufficiently verify user permissions before executing actions on protected resources. The vulnerability enables what is commonly referred to as horizontal privilege escalation in terms of data visibility rather than administrative command execution. By exploiting this flaw, an attacker can extract sensitive information that should remain isolated from lower-level users. This may include internal network topology details, configuration snippets containing potential secrets or keys, logs revealing operational patterns, or other system metadata. The ability to view these files provides a significant foothold for further reconnaissance activities within the managed environment.
The operational impact of this vulnerability is substantial because it compromises the confidentiality and integrity of the management plane. Network administrators rely on Fabric Composer to maintain secure boundaries between different levels of access to ensure that only authorized personnel can modify critical settings or view sensitive network maps. When an operator user can bypass these restrictions, they gain unauthorized insight into the broader infrastructure architecture. This information could be leveraged by attackers to plan more sophisticated attacks against higher-privileged accounts or specific network devices. For instance knowledge gained from viewing system files might reveal default credentials, internal IP addressing schemes, or security policies that are not yet hardened. Consequently, this undermines the principle of least privilege and exposes the organization to potential data exfiltration and deeper penetration into their IT infrastructure.
In alignment with industry standards, this vulnerability maps directly to CWE-269 Improper Privilege Management within the Common Weakness Enumeration framework. It also corresponds to MITRE ATT&CK technique T1078 Valid Accounts, as exploitation requires legitimate credentials, and potentially T1530 Data from Local System, depending on the specific files accessed. To mitigate this risk, HPE has released patches that correct the authorization logic in the API layer. Administrators should immediately apply these updates to all instances of Fabric Composer within their environment. Additionally, organizations should review their role-based access control policies to ensure that operator accounts are strictly limited to necessary functions and do not possess any residual permissions that could be exploited through similar flaws. Regular auditing of user activity logs for anomalous API calls can also help in detecting potential exploitation attempts before significant damage occurs.