#VU17727 Information disclosure in JForum - CVE-2019-7550

Vulnerability identifier: #VU17727

Vulnerability risk: Low

CVSSv4.0: 7.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/U:Clear]

CVE-ID: CVE-2019-7550

CWE-ID: CWE-200

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
JForum
Web applications / Forum & blogging software

Vendor: jforum.net

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists in the create user function due to the way the software handles messages based on username validity. A remote attacker can send mass register/check/username?username= requests to access sensitive information, such as valid usernames, to enumerate within the customer environment.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

JForum: 2.1.8

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External links
https://www.criticalstart.com/2019/02/information-disclosure-in-jforum-2-1-x-syntax/

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.