All versions of the package decompress are vulnerable to Arbitrary File Write via Archive Extraction (Zip Slip) when extracting a ZIP archive containing two entries with the same path - the first being a symlink to an arbitrary target and the second being a regular file - the file content is written through the symlink to the target location outside the output directory. This is due to the microtask processing order that checks readlink for the second file before resolving symlink for the first file. An attacker can write arbitrary file on the host filesystem potentially leading to remote code execution by providing a specially crafted ZIP archive.
**Note:**
This bypasses all existing path traversal protections including preventWritingThroughSymlink, added as a part of the fix for [CVE-2020-12265](https://security.snyk.io/vuln/SNYK-JS-DECOMPRESS-557358).
2. decompress: Decompress: Arbitrary file write leading to remote code execution via crafted ZIP archive (Zip Slip)
A flaw was found in the decompress package. A remote attacker can exploit this by providing a crafted ZIP archive with two entries at the same path: a symlink to an arbitrary target and a regular file. Due to microtask processing order, the file content is written through the symlink before it is resolved, allowing writes outside the output directory. This Zip Slip bypasses path traversal protections including preventWritingThroughSymlink (CVE-2020-12265) and can lead to remote code execution.