Reading Between the Code Lines: On the Use of Self-Admitted Technical Debt for Security Analysis
Static Analysis Tools (SATs) are central to security engineering activities, as they enable early identification of code weaknesses without requiring execution. However, their effectiveness is often limited by high false-positive rates and incomplete coverage of vulnerability classes. At the same time, developers frequently document security-related shortcuts and compromises as Self-Admitted Technical Debt (SATD) in software artifacts, such as code comments. While prior work has recognized SATD as a rich source of security information, it remains unclear whether -and in what ways- it is utilized during SAT-aided security analysis. OBJECTIVE: This work explores whether and how the security-related information encoded in SATD provides complementary security insights to SATs. METHOD: We followed a mixed-methods approach comprising (i) the analysis of a manually curated, SATD-annotated vulnerability dataset using three SATs and (ii) an online survey involving 72 security-aware software practitioners. RESULTS: The selected SATs flagged 114 of the 135 validated Security-related SATD instances (SSATD), yet the overlap between SAT-derived and manually mapped Common Weakness Enumeration (CWE) identifiers was only 6.42%, indicating that both sources often expose different kinds of security information. In particular, SSATD captured several dynamic and context-dependent weakness types that SATs commonly overlook or struggle to detect. Survey responses further indicate that practitioners rely on SSATD to contextualize SAT findings by understanding their impact, root causes, and potential fixes. IMPLICATIONS: Our findings suggest that SSATD constitutes a valuable and cost-effective source of complementary security knowledge that can support the interpretation, prioritization, and further assessment of SAT findings.