Vulnerability in WordPress Live Chat Plugin allows to steal and hijack sessions

Security researchers at Alert Logic have discovered a vulnerability in the WordPress Live Chat plugin that could be exploited to steal and hijack sessions.

Experts at Alert Logic have discovered a vulnerability in the popular WordPress Live Chat plugin that could be exploited by an unauthorized remote attacker to steal chat logs or manipulate chat sessions.

The critical vulnerability, tracked as CVE-2019-12498, is a critical authentication bypass issue (CWE-287 / OWASP Top 10: A2: 2017-Broken Authentication) that affects version 8.0.32 and earlier of the plugin.

The vulnerability is caused by the improper validation check for authentication, the attacker can trigger it to access restricted REST API endpoints.

“we uncovered a critical authentication bypass (CWE-287 / OWASP Top 10: A2: 2017-Broken Authentication) in version 8.0.32 and earlier.” reads the security advisory published by the experts. “This bypass allows an attacker to gain access to the REST API functionality without valid credentials—enabling exfiltration of chat logs and the ability to manipulate chat sessions.”

WP Live Chat Support provides customer support and chat with visitors through their WordPress websites, over 50,000 businesses currently use this plugin.

“The restricted REST API endpoints of the affected versions of WP Live Chat are vulnerable to abuse by unauthenticated remote attackers due to a flaw in the ‘wplc_api_permission_check()’ function.” continues the advisory.

The REST API endpoints of unpatched WP Live Chat Support installs are potentially exposed to attacks carried out by unauthenticated remote attackers due to vulnerability in the ‘wplc_api_permission_check()’ function.”

“The above series of ‘register_rest_route()’ calls define those REST API endpoints which should have access restrictions due to the nature of the functionality they expose,” continues the Alert Logic research team.

“Each restricted endpoint shares the same ‘permission_callback’ function, namely the ‘wplc_api_permission_check()’ function which will be explored shortly.”

A remote attacker can exploit exposed endpoints for several malicious purposes, including:

stealing the entire chat history for all chat sessions,
modifying or deleting the chat history,
injecting messages into an active chat session, posing as a customer support agent,
forcefully ending active chat sessions, as part of a denial of service (DoS) attack.

Below the timeline of the vulnerability:

Initial contact with vendor	28 May 2019
Vulnerability disclosed to vendor	29 May 2019
Vendor accepts vulnerability. Begins working on patch	30 May 2019
Submit to NVD. CVE assigned	31 May 2019
New version released. Confirmed no longer vulnerable	31 May 2019
Responsible Disclosure embargo lifted	10 June 2019

Fortunately, experts are not are of attacks in the wild exploiting the vulnerability.

[adrotate banner=”9″]

[adrotate banner=”12″]

Pierluigi Paganini

(SecurityAffairs – WordPress Live Chat plugin, hacking)

[adrotate banner=”5″]

[adrotate banner=”13″]

Pierluigi Paganini

Pierluigi Paganini is member of the ENISA (European Union Agency for Network and Information Security) Threat Landscape Stakeholder Group and Cyber G7 Group, he is also a Security Evangelist, Security Analyst and Freelance Writer. Editor-in-Chief at "Cyber Defense Magazine", Pierluigi is a cyber security expert with over 20 years experience in the field, he is Certified Ethical Hacker at EC Council in London. The passion for writing and a strong belief that security is founded on sharing and awareness led Pierluigi to find the security blog "Security Affairs" recently named a Top National Security Resource for US. Pierluigi is a member of the "The Hacker News" team and he is a writer for some major publications in the field such as Cyber War Zone, ICTTF, Infosec Island, Infosec Institute, The Hacker News Magazine and for many other Security magazines. Author of the Books "The Deep Dark Web" and “Digital Virtual Currency and Bitcoin”.