Multiple vulnerabilities in Joomla!

1) Cross-site scripting

EUVDB-ID: #VU52170

Risk: Medium

CVSSv3.1: 5.3 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-26030

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

Exploit availability: No

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 passed via the logo parameter of the default templates on error pages. 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 updates from vendor's website.

Vulnerable software versions

Joomla!: 3.0.0 - 3.9.25

External links

http://developer.joomla.org/security-centre/850-20210401-core-escape-xss-in-logo-parameter-error-pages.html

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.

2) PHP file inclusion

EUVDB-ID: #VU52172

Risk: Medium

CVSSv3.1: 6.3 [CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-26031

CWE-ID: CWE-98 - Improper Control of Filename for Include/Require Statement in PHP Program

Exploit availability: No

Description

The vulnerability allows a remote user to include and execute arbitrary PHP files on the server.

The vulnerability exists due to incorrect input validation when including PHP files on module layout settings. A remote user can send a specially crafted HTTP request to the affected application, include and execute arbitrary PHP code on the system with privileges of the web server.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Joomla!: 3.0.0 - 3.9.25

External links

http://developer.joomla.org/security-centre/851-20210402-core-inadequate-filters-on-module-layout-settings.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated privileged user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.