diff --git a/servers/slapd/schema_init.c b/servers/slapd/schema_init.c
index 4668996251610dd79861de2e70244d82ef5fa9f2..914df70ebac9ed79fba62287165ba5d8621e0ede 100644
--- a/servers/slapd/schema_init.c
+++ b/servers/slapd/schema_init.c
@@ -3975,6 +3975,8 @@ issuerAndThisUpdateCheck(
 					break;
 				}
 			}
+			if ( tu->bv_len < STRLENOF("YYYYmmddHHmmssZ") ) return LDAP_INVALID_SYNTAX;
+
 			x.bv_val += tu->bv_len + 1;
 			x.bv_len -= tu->bv_len + 1;