Ethical Hacking News
The Comment2Shell vulnerability in WordPress is a critical vulnerability that exposes websites to remote code execution. In this article, we will explore the details of this vulnerability, its implications, and the steps that website owners can take to protect their sites. We will also discuss the severity of the vulnerability, its potential impact on websites, and the measures that can be taken to prevent remote code execution.
WordPress's Comment2Shell vulnerability allows an anonymous visitor to execute remote code on a website's server. A vulnerability was discovered in WordPress's comment handling mechanism by security researcher Rafie Muhammad. The vulnerability can be exploited to inject malicious HTML code that runs automatically as the page loads, without requiring a user to click on it. If a logged-in administrator opens a page carrying a malicious comment, the script can use the administrator's session to upload a plugin containing a web shell. The attack depends on the site's comment display settings and can occur even if the comment has not been approved. WordPress has already fixed the vulnerability in version 7.1.1 and advises users to update their sites to this version as soon as possible. Users can protect their sites by updating to version 7.1.1 or disabling comments on posts.
The cybersecurity world was recently shaken by the revelation of a critical vulnerability in WordPress, a content management system (CMS) that powers over 60 million websites worldwide. The vulnerability, dubbed "Comment2Shell" by Patchstack, a company that assigns security bug identifiers, is a serious flaw in WordPress's comment handling mechanism that can be exploited by an anonymous visitor to execute remote code on a website's server. In this article, we will delve into the details of this vulnerability, its implications, and the steps that website owners can take to protect their sites.
The Comment2Shell vulnerability was discovered by security researcher Rafie Muhammad, who reported it to WordPress and Patchstack. The flaw was found in WordPress's comment handling mechanism, which involves checking comments for dangerous HTML and reformating them when displayed on the page. However, the vulnerability exploited a gap between these two steps, allowing an attacker to inject malicious HTML code that would run automatically as the page loaded, without requiring a user to click on it.
The script ran in the browser of whoever opened the page, whether or not they were logged in, and it acted with that person's access level to the site. In other words, if a logged-in administrator opened the page carrying the comment, the script could then use the administrator's own session to upload a plugin containing a web shell, a small file that executes whatever commands an attacker sends. This is a known route from an administrator's browser to control of the server.
The attack also depended on how a site displayed its comments. It worked on sites that use a block theme, or a classic theme that formats comments the same way, and not on others. For any of this to happen, the comment had to appear on the page first. WordPress described the flaw as exploitable only "subject to comment approval." However, comment moderation is off by default, and the setting that holds a first-time commenter can be worked around, so a comment could reach the page without anyone approving it.
In other words, if a site had a setting that allowed first-time commenters to post without moderation, and an attacker were to craft a comment that exploited the Comment2Shell vulnerability, that comment would still be displayed on the page, regardless of whether it had been approved or not.
Fortunately, WordPress has already fixed the vulnerability in version 7.1.1, and users are advised to update their sites to this version as soon as possible. Patchstack, the company that assigned the identifier to the vulnerability, rated it 7.1 out of 10 on the CVSS scale, indicating that it is a high-severity vulnerability.
While the Comment2Shell vulnerability is a serious issue, it is worth noting that there is currently no evidence to suggest that it has been exploited in real-world attacks. However, given the severity of the vulnerability and its potential impact on websites, it is essential that users take immediate action to protect their sites.
To protect their sites, users can follow the steps outlined by WordPress and Patchstack. First and foremost, they should update their WordPress sites to version 7.1.1 or the latest release on their branch, if it still gets security fixes. The affected versions run from 4.7 through 7.1, and these are the fixed releases for the current branches.
Users who cannot update at once can shut the way in by closing comments on posts or turning comments off across their site, and a web application firewall or a security plugin may block the crafted comment. However, neither WordPress nor the researcher published a separate workaround, so users are advised to update their sites to the latest version as soon as possible.
In conclusion, the Comment2Shell vulnerability is a serious issue that highlights the importance of keeping software up to date. By updating their WordPress sites to version 7.1.1 or the latest release on their branch, users can protect their sites from potential attacks and prevent remote code execution.
Related Information:
https://www.ethicalhackingnews.com/articles/WordPress-Comment2Shell-Flaw-A-Critical-Vulnerability-that-Exposes-Websites-to-Remote-Code-Execution-ehn.shtml
https://thehackernews.com/2026/09/wordpress-comment2shell-flaw-can-turn.html
Published: Tue Sep 22 03:10:17 2026 by llama3.2 3B Q4_K_M
