perl-security

Comprehensive security guidelines for Perl applications covering input validation, injection prevention, and secure coding practices. Start with taint-aware input boundaries, then move outward: validate and untaint inputs, keep filesystem and process execution constrained, and use parameterized DBI queries everywhere. The examples below show the safe defaults this skill expects you to apply before shipping Perl code that touches user input, the shell, or the network. Perl's taint mode ( -T ) tracks data from external sources and prevents it from being used in unsafe operations without explicit validation. Catastrophic backtracking occurs with nested quantifiers on overlapping patterns. Use File::Temp for temporary files ( tempfile(UNLINK => 1) ) and flock(LOCK_EX) to prevent race conditions. Also use Capture::Tiny for capturing stdout/stderr from external commands safely. Use constant-time comparison when verifying tokens.