LiteSpeed Web Server vulnerabilities discovered by researchers at Palo Alto Networks can be exploited to take complete control of a targeted server.
The security holes were discovered during an audit of OpenLiteSpeed, the open source version of the LiteSpeed performance-focused web server made by LiteSpeed Technologies. Both versions are impacted by the vulnerabilities and they have been patched with the release of OpenLiteSpeed 220.127.116.11 and LiteSpeed 6.0.12.
LiteSpeed is a popular web server and an analysis by Palo Alto Networks showed that it has a 2% market share — others say that it has a much bigger market share — and that it is used by 1.9 million internet-facing instances.
The vulnerabilities discovered by the security firm’s researchers can be exploited to compromise the targeted web server and execute arbitrary code with elevated privileges.
However, the flaws cannot be exploited without authentication. The attacker must first use a brute-force attack or social engineering to obtain valid credentials to the web server’s dashboard.
The first vulnerability, rated ‘high severity’ and tracked as CVE-2022-0073, is related to a field that allows users to specify a command to be executed when the server starts.
“This functionality is considered dangerous and therefore mitigations for abusing it were implemented. We managed to bypass the mitigations and abuse this functionality to download and execute a malicious file on the server with the privileges of the user nobody, which is an unprivileged user that traditionally exists in Linux machines,” Palo Alto Networks explained.
The second vulnerability, also rated ‘high severity’ and tracked as CVE-2022-0074, can be leveraged by an attacker who has exploited the previous flaw to escalate privileges from ‘nobody’ to ‘root’.
The third issue, CVE-2022-0072, is a directory traversal bug that can be exploited to bypass security measures and access forbidden files.
“An attacker that compromised the server could create a secret backdoor and exploit the vulnerability to access it,” the security firm said.
Patches were released roughly two weeks after Palo Alto Networks reported its findings to LiteSpeed developers.