Path Traversal in Izpack

CVE-2026-54550

IzPack is a widely used tool for packaging applications on the Java platform as cross-platform installers. In 5.2.6 and earlier, UnpackerBase.unpack() in izpack-installer/src/main/java/com/izforge/izpack/installer/unpacker/UnpackerBase.java obtains an attacker-controlled PackFile targetPath, passes it through IoHelper.translatePath(), which only converts separators, and constructs a File without normalizing parent-directory segments or enforcing destination containment. A malicious installer pack entry containing ../ sequences can therefore write outside the intended installation directory to startup folders, executable search paths, or other locations accessible with the victim's privileges when the victim runs the installer.

Vulnerability class: Path Traversal (Directory Traversal)