Multiple vulnerabilities in Composr CMS

Published: 2021-04-12

Risk	High
Patch available	YES
Number of vulnerabilities	2
CVE-ID	CVE-2021-30150 CVE-2021-30149
CWE-ID	CWE-79 CWE-434
Exploitation vector	Network
Public exploit	Public exploit code for vulnerability #1 is available. Public exploit code for vulnerability #2 is available.
Vulnerable software Subscribe	Composr CMS Web applications / CMS
Vendor	ocProducts

Security Bulletin

This security bulletin contains information about 2 vulnerabilities.

1) Cross-site scripting

EUVDB-ID: #VU52054

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-2021-30150

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 data in the "ajax_tree.php" script. A remote attacker can trick the victim to follow a 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

Composr CMS: 10.0.36

External links

http://packetstormsecurity.com/files/162111/Composr-CMS-10.0.36-Cross-Site-Scripting.html
http://gitlab.com/composr-foundation/composr/commit/833a06466

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.

2) Arbitrary file upload

EUVDB-ID: #VU52056

Risk: High

CVSSv3.1: 8.8 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2021-30149

CWE-ID: CWE-434 - Unrestricted Upload of File with Dangerous Type