The servlet gateway in IBM Cognos Business Intelligence 8.4.1 before IF3, 10.1.0 before IF4, 10.1.1 before IF4, 10.2.0 before IF4, 10.2.1 before IF2, and 10.2.1.1 before IF1 allows remote attackers to cause a denial of service (temporary gateway outage) via crafted HTTP requests.