WWW::OAuth 1.000 and earlier for Perl uses the rand() function as the default source of entropy, which is not cryptographically secure, for cryptographic functions.
https://security.metacpan.org/docs/guides/random-data-for-security.html
https://perldoc.perl.org/functions/rand
https://metacpan.org/release/DBOOK/WWW-OAuth-1.000/source/lib/WWW/OAuth.pm#L86