The vulnerability in question is CVE-2007-4559, initially described as a directory traversal vulnerability in Python’s ‘tarfile’ module that could allow an attacker to remotely overwrite arbitrary files by convincing users to process specially crafted tar archives.

The flaw was never properly patched and instead users were warned not to open archive files from untrusted sources.

Researchers at Trellix have now shown that an attacker can exploit the vulnerability to write arbitrary files and from there achieve malicious code execution in most cases. They demonstrated this against several popular applications that use the vulnerable Python module, even showing how an attacker could use social engineering to execute arbitrary code on the targeted system with administrator privileges.