In Net::OAuth::Client in the Net::OAuth package before 0.29 for Perl, the default nonce is a 32-bit integer generated from the built-in rand() function, which is not cryptographically strong.
https://metacpan.org/release/RRWO/Net-OAuth-0.29/changes
https://metacpan.org/release/KGRENNAN/Net-OAuth-0.28/source/lib/Net/OAuth/Client.pm#L260