Vulnerability identifier: #VU50169

Vulnerability risk: High

CVSSv3.1: 9.6 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:F/RL:U/RC:C]

CVE-ID: CVE-2020-35729

CWE-ID: CWE-78

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
KLog Server
Server applications / Other server solutions

Vendor: klogserver.com

Description

The vulnerability allows a remote attacker to execute arbitrary shell commands on the target system.

The vulnerability exists due to improper input validation in the "user" parameter in actions/authenticate.php. A remote unauthenticated attacker can pass specially crafted data to the application and execute arbitrary OS commands on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

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

Vulnerable software versions

KLog Server: 2.4.1

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External links
http://packetstormsecurity.com/files/160798/Klog-Server-2.4.1-Command-Injection.html
http://packetstormsecurity.com/files/161123/Klog-Server-2.4.1-Command-Injection.html
http://github.com/mustgundogdu/Research/blob/main/KLOG_SERVER/Exploit_Code
http://github.com/mustgundogdu/Research/blob/main/KLOG_SERVER/README.md

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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, a fully functional exploit for this vulnerability is available.