The bug is located in the IO::Compress zipdetails command line tool, not in the library functions used by application code. When the tool processes an Info‑ZIP Unix Extra Field containing an 8‑byte UID or GID, an undefined subroutine error occurs, causing the program to terminate with exit status 255. The crash does not allow arbitrary code execution, but it does prevent the tool from completing, which can interrupt scripts or user operations relying on zipdetails.

This issue affects the PMQS IO::Compress Perl module versions 2.207 up to and including 2.219. It specifically impacts the bundled zipdetails command line utility; users of IO::Uncompress or other callers of IO::Compress are not impacted.

Based on the description, it is inferred that the flaw exists only in the command line tool, so an attacker would need to execute zipdetails within the context of a user or application that invokes it. The exposure is local, with a limited scope of potential denial of service. The EPSS score of < 1% indicates that the probability of exploitation is very low; combined with the lack of real‑world reports, the risk remains moderate. Nonetheless, the impact of a crash warrants prompt patching, and the issue should be considered a high‑priority mitigation.