Archive::Tar versions before 3.08 for Perl extract hardlinks to attacker controlled paths outside the extraction directory. _make_special_file() passes the tar header's linkname to link() without validating it against absolute paths or .. segments, creating a hardlink that shares the victim file's inode. A subsequent write through the extracted name modifies the victim file, and the post-extraction chmod, chown, and utime block in _extract_file() (guarded only against symlinks via -l) applies
Archive::Tar versions before 3.08 for Perl extract hardlinks to attacker controlled paths outside the extraction directory.
_make_special_file() passes the tar header's linkname to link() without validating it against absolute paths or .. segments, creating a hardlink that shares the victim file's inode.
A subsequent write through the extracted name modifies the victim file, and the post-extraction chmod, chown, and utime block in _extract_file() (guarded only against symlinks via -l) applies the tar header's mode, owner, and timestamps to the shared inode during extraction alone.
Why this VPI (explainable, experimental)
VPI breakdown
| Impact | 75.00 |
| Exploitation signal(No additional exploitation signal) | ×1.00 |
| VPI | 75.00 |
VPI formula vpi-v1