Date::Manip versions <=6.99 for Perl use regexes that match Unicode decimal digits (\p{Nd}) instead of strictly ASCII digits ([0-9]) for year, month, and day fields. The numeric validation uses Perl's numification, which truncates strings at the first non-ASCII digit, allowing crafted inputs with trailing non-ASCII digits to pass validation but produce incorrect numeric values. This results in parsed dates that differ from the original input without triggering parse errors. Hour, minute, and second fields are not affected due to stricter ASCII digit matching. This improper validation of unsafe equivalence in input can lead to silent corruption of date values used in critical logic.

Applications using Date::Manip to parse untrusted input may receive silently corrupted date values that differ from the original input string. This can cause incorrect behavior in logic that depends on accurate date parsing, such as expiry checks or retention windows, potentially leading to security or business logic errors. No known exploits are reported in the wild.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid passing untrusted input containing non-ASCII decimal digits to Date::Manip parsing functions. Consider input validation or sanitization to restrict date input to ASCII digits only.