The SPIP refererspam plugin versions prior to 1.3.0 contain an unauthenticated SQL injection vulnerability in the refererspamajouter and refererspamsupprimer action handlers. The handlers read the url parameter from a GET request and interpolate it directly into SQL LIKE clauses without input validation or parameterization. The endpoints do not enforce authorization checks and do not use SPIP action protections such as securiseraction(), allowing remote attackers to execute arbitrary SQL queries.