CVE-2026-27606
CriticalCVSS 9.8Exploitation Probability (EPSS)
Elevated risk70th percentile - higher than 70% of all known CVEs
Summary
Rollup, a JavaScript module bundler, contains an Arbitrary File Write vulnerability via Path Traversal. Insecure file name sanitization allows an attacker to use traversal sequences (../) to overwrite files anywhere on the host filesystem. Versions prior to 2.80.0, 3.30.0, and 4.59.0 are affected.
Risk Assessment
The risk is persistent Remote Code Execution (RCE) by overwriting critical system or user configuration files. An attacker could gain control over the build environment.
Recommendation
Immediately upgrade Rollup to version 2.80.0, 3.30.0, or 4.59.0 depending on your branch. If an upgrade is not possible, restrict trust in input that controls output filenames.
Original NVD description (English source)
Rollup is a module bundler for JavaScript. Versions prior to 2.80.0, 3.30.0, and 4.59.0 of the Rollup module bundler (specifically v4.x and present in current source) is vulnerable to an Arbitrary File Write via Path Traversal. Insecure file name sanitization in the core engine allows an attacker to control output filenames (e.g., via CLI named inputs, manual chunk aliases, or malicious plugins) and use traversal sequences (`../`) to overwrite files anywhere on the host filesystem that the build process has permissions for. This can lead to persistent Remote Code Execution (RCE) by overwriting critical system or user configuration files. Versions 2.80.0, 3.30.0, and 4.59.0 contain a patch for the issue.