CVE-2026-69153 PostCSS: incomplete fix of CVE-2026-45623 — attacker-controlled sourceMappingURL reads arbitrary .map files when `from` is unset

PostCSS takes a CSS file and provides an API to analyze and modify its rules by transforming the rules into an Abstract Syntax Tree. Prior to 8.5.19, if from is unset, an attacker can cause PreviousMap.loadFile to read an unintended source-map file by supplying an absolute or directory-traversal...