adm-zip allocates an entry's output buffer from the declared uncompressed size (central-directory size field) before validating it against the actual data. A tiny crafted ZIP that declares a huge uncompressed size forces a multi-gigabyte allocation from a few bytes.
adm-zip 0.5.9 through 0.6.0 follows symbolic links at the extraction destination. Utils.sanitize in util/utils.js enforces containment by comparing only the string form of an archive entry name against the resolved extraction root, and Utils.writeFileTo opens the computed destination with fs.openSync(path, "w", 0o666), which resolves symbolic links and carries neither O_NOFOLLOW nor a pre-write fs.lstatSync check. When a path component at the destination already exists as a symbolic link pointing outside …
adm-zip before 0.5.18 is vulnerable to denial of service via a crafted ZIP file with a manipulated uncompressed size header field. In zipEntry.js line 103, Buffer.alloc(_centralHeader.size) allocates memory based on the declared uncompressed size from the ZIP central directory header without validating it against the actual compressed data size or imposing any upper bound. The size value is read directly from the binary header at entryHeader.js line 266 with no …
The adm-zip npm library is vulnerable to directory traversal, allowing attackers to write to arbitrary files via a ../ in a Zip archive entry that is mishandled during extraction.