CVE-2026-40491: gdown Affected by Arbitrary File Write via Path Traversal in gdown.extractall

The gdown library (tested on v5.2.1) is vulnerable to a Path Traversal attack within its extractall functionality. When extracting a maliciously crafted ZIP or TAR archive, the library fails to sanitize or validate the filenames of the archive members. This allow files to be written outside the intended destination directory, potentially leading to arbitrary file overwrite and Remote Code Execution (RCE).