Vulnerability identifier: #VU54578

Vulnerability risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-26038

CWE-ID: CWE-284

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Joomla!
Web applications / CMS

Vendor: Joomla!

Description

The vulnerability allows a remote user to gain unauthorized access to otherwise restricted functionality.

The vulnerability exists due to improper access restrictions within the com_installer component. the iInstall action in com_installer lacks the required hardcoded ACL checks for superusers. A remote unprivileged user can compromise the affected installation of Joomla! under certain circumstances.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Joomla!: 3.9.0 - 3.9.27, 3.8.0 - 3.8.13, 3.7.0 - 3.7.5, 3.6.0 - 3.6.5, 3.5.0 - 3.5.9, 3.0.0 - 3.0.4, 3.3.0 - 3.3.6, 3.2.0 - 3.2.7, 3.4.0 - 3.4.8, 3.1.0 - 3.1.6, 2.5.0 - 2.5.28

---

External links
http://developer.joomla.org/security-centre/859-20210704-core-privilege-escalation-through-com-installer.html

---

Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

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