A vulnerability classified as critical was found in Beijing Yunfan Internet Technology Yunfan Learning Examination System 1.9.2. Affected by this vulnerability is an unknown functionality of the file src/main/java/com/yf/exam/modules/sys/user/controller/SysUserControl of the component JWT Token Handler. The manipulation leads to improper authentication. The attack can be launched remotely. The complexity of an attack is rather high. The exploitation appears to be difficult. The exploit has been disclosed to the public and may be used.

A vulnerability classified as problematic has been found in Beijing Yunfan Internet Technology Yunfan Learning Examination System 1.9.2. Affected is an unknown function of the file src/main/java/com/yf/exam/modules/paper/controller/PaperController.java， of the component Exam Answer Handler. The manipulation leads to information disclosure. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used.

A vulnerability was found in Beijing Yunfan Internet Technology Yunfan Learning Examination System 1.9.2. It has been rated as critical. This issue affects some unknown processing of the file /doc.html. The manipulation leads to improper authorization. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used.

An issue in Beijing Yunfan Internet Technology Co., Ltd, Yunfan Learning Examination System v.6.5 allows a remote attacker to obtain sensitive information via the password parameter in the login function.