Business::GoCardless versions before 1.01 for Perl accept forged webhooks when a configured webhook secret is undef or empty. signature_valid uses each configured secret as the HMAC key, and nothing rejects undef or an empty string, both of which Digest::SHA treats as an empty key. A secret read from an unset environment variable, or an empty entry in a list of rotated secrets, is used as is. A remote attacker can sign a forged webhook with an empty key and have it accepted as sent by GoCardless.
Fix
Nothing published yet: no patch, vendor advisory or mitigation reference on NVD, no vendor advisory in the News for this CVE, not in CISA's KEV, no fixed package version. BaselineWatch does not guess at one.
Change history 1
- First seenunscoredNVD modified 2026-10-30 12:56
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.