Title: H3C SSL VPN Username Enumeration
Advisory ID: ZSL-2022-5697
Type: Local/Remote
Impact: Exposure of Sensitive Information
Risk: (2/5)
Release Date: 12.02.2022

Summary

H3C SSL VPN is a secure VPN system based on SSL connections. It allows mobile employees to access corporate networks remotely in an easy and secure way. The H3C SSL VPN devices are a new generation of professional SSL VPN devices for enterprises. They can function as ingress gateways as well as proxy gateways of internal server clusters. The SecPath SSL VPN devices are for small-to medium-sized enterprises, while the SecBlade SSL VPN devices are for medium-sized enterprises.

Description

The weakness is caused due to the login script and how it verifies provided credentials. An attacker can use this weakness to enumerate valid users on the affected application via 'txtUsrName' POST parameter.

Vendor

Hangzhou H3C Technologies Co. | New H3C Technologies Co., Ltd. - https://www.h3c.com

Affected Version

N/A

Tested On

ssl vpn gateway HttpServer 1.1

Vendor Status

N/A

PoC

h3c_userenum.txt

Credits

Vulnerability discovered by Gjoko Krstic - <gjoko@zeroscience.mk>

References

[1] https://www.exploit-db.com/exploits/50742
[2] https://packetstormsecurity.com/files/165977/H3C-SSL-VPN-Username-Enumeration.html
[3] https://cxsecurity.com/issue/WLB-2022020072
[4] https://exchange.xforce.ibmcloud.com/vulnerabilities/219535

Changelog

[12.02.2022] - Initial release
[16.02.2022] - Added reference [1], [2], [3] and [4]

Contact

Zero Science Lab

Web: https://www.zeroscience.mk
e-mail: lab@zeroscience.mk