CVE-2026-45623 PostCSS: Arbitrary file read and information disclosure via attacker-controlled sourceMappingURL in CSS comments

PostCSS takes a CSS file and provides an API to analyze and modify its rules by transforming the rules into an Abstract Syntax Tree. In versions 8.5.11 and prior, the PreviousMap parses the / sourceMappingURL=PATH / comment from any CSS string passed to process and dereferences PATH against the...

CVE-2026-45623

CVE-2026-45623 affects PostCSS ≤ 8.5.11. The bug lives in the PreviousMap logic used during CSS processing: the sourceMappingURL comment is parsed without any scheme, allowlist, or traversal checks, and the attacker-controlled path is dereferenced to read files readable by the Node process. This ...

NPM: PostCSS: Arbitrary file read and information disclosure via attacker-controlled sourceMappingURL in CSS comments

NPM: PostCSS: Arbitrary file read and information disclosure via attacker-controlled sourceMappingURL in CSS comments vulnerability discovered by ? in WordPress Npm postcss versions = 8.5.11...

CVE-2026-49356

Babel is a compiler for writing next generation JavaScript. Prior to 8.0.0-rc.6 and 7.29.6, @babel/core affected by an arbitrary file read via a sourceMappingURL comment. Using @babel/core to compile maliciously crafted code can allow an attacker to read any source map from the system that is...

CVE-2026-49356 Babel: Arbitrary File Read via sourceMappingURL Comment in @babel/core

Babel is a compiler for writing next generation JavaScript. Prior to 8.0.0-rc.6 and 7.29.6, @babel/core affected by an arbitrary file read via a sourceMappingURL comment. Using @babel/core to compile maliciously crafted code can allow an attacker to read any source map from the system that is...

CVE-2026-49356

CVE-2026-49356 affects @babel/core (Babel) prior to versions 8.0.0-rc.6 and 7.29.6. The issue allows an arbitrary file read via a sourceMappingURL comment in the input code, enabling reading of source maps from the system running Babel when the attacker controls the input source code and knows th...

@babel/core: Arbitrary File Read via sourceMappingURL Comment

Impact Using @babel/core to compile maliciously crafted code can allow ab attacker to read any source map from the system that is running Babel, if these conditions are all true: - the attacker controls the input source code - the attacker can read the output source code - the attacker knows the...