SQRL Login Security & Risk Analysis

The static analysis of sqrl-login v2.1.0 reveals a plugin with a seemingly minimal attack surface, reporting zero AJAX handlers, REST API routes, shortcodes, or cron events. This absence of direct entry points is a positive security indicator. Furthermore, the code signals show no dangerous functions, file operations, or external HTTP requests. All SQL queries utilize prepared statements, and there are no known vulnerabilities (CVEs) in its history. The plugin also appears to handle output escaping reasonably well, with 70% of outputs being properly escaped.

However, a significant concern arises from the taint analysis, which identified 3 flows with unsanitized paths. While no critical or high severity issues were reported in this taint analysis, unsanitized paths are a strong indicator of potential vulnerabilities, especially if they involve user-supplied input that is not properly validated or escaped before being used. The absence of nonce and capability checks across all entry points (even though there are none reported) is a methodological weakness, as any future addition of entry points would be unprotected by default. The lack of documented vulnerabilities in the history is good, but it could also indicate limited testing or analysis, and the taint analysis results suggest areas that warrant further investigation.

In conclusion, while sqrl-login v2.1.0 presents a clean slate in terms of known vulnerabilities and a small attack surface, the presence of unsanitized paths in the taint analysis is a critical area of concern that should be addressed. The plugin's good practices in SQL and absence of dangerous functions are commendable, but the potential for exploitation due to unsanitized paths, coupled with the lack of explicit authorization checks on its (albeit zero) entry points, prevents a full security endorsement.