Flawfinder output manipulation via untrusted filenames and source text

Summary

Flawfinder is a a static analysis tool for finding vulnerabilities in C/C++ source code. Versions prior to 2.0.20 have an improper input neutralization issue leading to output manipulation, specifically, Terminal/ANSI Escape Sequence Injection and XML Injection. A malicious file whose name contains ANSI escape sequences can end up being included in flawfinder's standard terminal output, with many effects. Untrusted fields (such as filenames, categories, or code context text) were not properly sanitized when generating structured reports. An attacker could exploit this to corrupt CSV formats or inject arbitrary XML attributes into SonarQube outputs via output_sonar(). It impacts those who use flawfinder to evaluate intentionally malicious filenames or file contents. This issue has been fully patched in Version 2.0.20 (released 2026-05-16). There is no configuration-based workaround within older versions of flawfinder. If an immediate upgrade is not possible, users can mitigate the risk by pre-scanning filenames, inspecting raw output, and/or restricting untrusted inputs.