Threats affecting pkg:github/enspirit/elo

CVE-2026-44267 is a critical cross-site scripting (XSS) vulnerability in the Elo expression language used by enspirit. Versions prior to 1.0.1 allow attacker-controlled strings to execute arbitrary JavaScript code via the .constructor.constructor property. This flaw affects the defaultFormats.elo.parse() function, the bin/elo CLI, and the elo-lang.org/try playground, enabling browser script execution and session compromise. It also permits arbitrary Node.js code execution in environments using the library. The issue is fixed in version 1.0.1.

Elo is a purely functional expression language for no-code tools. Prior to 1.0.1, the Ruby backend in src/compilers/ruby.ts embeds attacker-controlled text in Ruby double-quoted strings without escaping #, so Ruby interpolation forms in the string-literal emitter or the labelled subtype-constraint branch become executable Ruby. The affected entry points include the /try playground with the Ruby target, bin/eloc -t ruby -x, and defaultFormats.elo.parse() followed by Ruby emission. A failing labelled subtype constraint evaluates its message, while an ordinary string literal is evaluated when the compiled Ruby runs, allowing Ruby code and shell command execution through backticks. JavaScript, Python, and SQL emission are not affected by this Ruby-specific path. This issue is fixed in version 1.0.1.

CVE-2026-44265 is an improper input validation vulnerability in enspirit elo versions prior to 1.0.1. The vulnerability arises because Elo's programmatic AST API accepts arbitrary values from untyped sources and interpolates them into generated code without runtime syntax validation. This affects multiple fields such as int_literal/float_literal values, variable names, member access properties, object literal keys, datapath segments, lambda parameter names, and SQL let binding names. Exploitation can lead to arbitrary code execution in JavaScript, Ruby, and Python environments, as well as SQL injection in SQL targets. The issue is fixed in version 1.0.1.