XS::Parse::Infix versions 0.40 through 0.49 for Perl contain a type confusion vulnerability due to improper reference checking in the wrapper function generated for list-associative infix operators. The function uses SvRV() to check if arguments are array references instead of the correct SvROK(), causing it to treat numbers as array references. This leads to dereferencing invalid memory locations, typically resulting in segmentation faults. Attackers supplying crafted input can influence the address dereferenced, potentially causing crashes or other unintended behavior. The vulnerability is demonstrated with the zip operator and specific argument lists.

The vulnerability can cause segmentation faults and crashes in applications using affected versions of XS::Parse::Infix. By supplying crafted input, an attacker may influence memory dereferencing, which could lead to denial of service or potentially other undefined behaviors. There is no confirmed evidence of exploitation in the wild or further impact such as code execution.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid processing untrusted input with affected versions of XS::Parse::Infix or apply application-level input validation to prevent passing numbers where array references are expected.