Client-Side Commercial Vendor Discovery

Client-Side Commercial Vendor Discovery is a reconnaissance sub-technique within Application Dependencies Mapping where attackers analyze traffic and available application binaries (across mobile, desktop, and on-prem environments) to identify third-party commercial software vendors in use. By examining network communications, API calls, embedded libraries, certificates, and binary signatures, adversaries can map the commercial software ecosystem supporting the target application. Furthermore, the presence of a known commercial vendor can signal a potential pivot point within the software supply chain, especially if the vendor is less mature or trusted implicitly via integration than the intended target. In parallel, public OSINT sources (e.g. marketing materials, case studies, job postings, or SOC 2 reports) can reveal formal relationships between a company and specific vendors, providing additional context for targeted exploitation.

Identifying commercial vendor integrations enables an attacker to keep the primary target in focus while exploiting the vendor as a weaker entry point. By leveraging trust relationships, exposed credentials, or insecure integration patterns, the attacker can gain indirect access to the target environment through a secondary target, bypassing potentially stronger front-line defenses. This technique is particularly effective because organizations often apply more rigorous security controls to their primary systems while treating vendor integrations as trusted third-party components with reduced scrutiny.