Cpanel::JSON::XS versions before 4.80 for Perl use freed filter callbacks when a filter removes itself during decoding in decode_hv. A decode copies the parser's filter_json_object and filter_json_single_key_object callbacks without taking references to them. A filter callback that removes the last single-key filter frees the callback table while the decode in progress still uses it. The next object is dispatched through freed memory and can crash the process.
https://metacpan.org/release/RURBAN/Cpanel-JSON-XS-4.80/changes
https://github.com/rurban/Cpanel-JSON-XS/commit/c3e7e3c5b0b72d82b072c6a7cfb8c34cec4c7ea2.patch