diff --git a/lib/SimpleSAML/Metadata/SAMLParser.php b/lib/SimpleSAML/Metadata/SAMLParser.php
index bd896f8eedcebf54ea13ac2742955fae7f543906..6b2031f4dc573c7182252accb41465c594511315 100644
--- a/lib/SimpleSAML/Metadata/SAMLParser.php
+++ b/lib/SimpleSAML/Metadata/SAMLParser.php
@@ -1284,6 +1284,7 @@ class SimpleSAML_Metadata_SAMLParser {
 				return TRUE;
 			} catch(Exception $e) {
 				/* Validation with this validator failed. */
+				SimpleSAML_Logger::debug('Validation of fingerprint failed: ' . $e->getMessage());
 			}
 		}