[GHSA] GHSA-m66c-fw79-6359 (medium) — eml_parser has parser DoS via deeply nested parentheses in e-mail headers

GHSA-m66c-fw79-6359 Severity: medium CVE: CVE-2026-55619

eml_parser has parser DoS via deeply nested parentheses in e-mail headers

### Summary

`eml_parser` uses the `email.utils.getaddresses()` function from the CPython standard library to parse e-mail headers that contain e-mail addresses (such as `To`, `Cc`, `Bcc`, `From`, `Reply-To`, `Sender`, ...). When the input header contains a deeply ne