XSS in Upcoming Events plugin for MyBB

1) Cross-site scripting

EUVDB-ID: #VU17931

Risk: Low

CVSSv3.1: 5.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:P/RL:O/RC:C]

CVE-ID: CVE-2019-9650

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Exploit availability: Yes

Description

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied input when processing data passed via a specially crafted name for an event in the "upcoming_events.php" script. A remote attacker can trick the victim to follow a specially specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Upcoming Events: 1.32

External links

http://community.mybb.com/mods.php?action=changelog&pid=1231
http://github.com/vintagedaddyo/MyBB_Plugin-Upcoming_Events/pull/1/commits/d0a0e1c6e56f248613e0150344ebea8764bba5fa

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.