Scans Target Wordfence WAF Script to Identify WordPress Sites
Attackers are scanning for the 'wordfence-waf.php' script on WordPress sites, potentially to enumerate Wordfence-protected installations and identify targets for exploitation.
Recent observations indicate a surge in scans specifically targeting the 'wordfence-waf.php' script, a component used by the popular Wordfence security plugin for WordPress websites. These scans, noted by the SANS Internet Storm Center, appear to be an effort by threat actors to identify WordPress sites that are actively protected by Wordfence.
The observed scan requests are minimal, often omitting standard headers like User-Agent and instead relying solely on the target site's IP address in the Host header. While the 'wordfence-waf.php' file itself does not contain sensitive information or configuration details, its presence signifies that a site is utilizing Wordfence's security measures. This information can be valuable to attackers seeking to understand a target's defenses.
One primary hypothesis for this activity is reconnaissance. By identifying Wordfence-protected sites, attackers can potentially gauge the effectiveness of their exploits against other, less protected targets. Wordfence is known to collect and publish intelligence on emerging threats, which can inadvertently 'burn' exploit techniques as they become widely known and defended against. Identifying sites that may not have the latest protections or configurations could allow attackers to bypass these defenses.
Another potential motive behind these scans is to circumvent Wordfence's protection mechanisms. By directly targeting the IP address of a website rather than its domain name, attackers might attempt to bypass Web Application Firewall (WAF) rules that are configured to inspect traffic based on hostnames. This could expose sites that rely on Wordfence for protection to direct attacks, especially if timely patches or specific configurations are not in place.
While WAFs and virtual patching offer crucial layers of defense, they are not infallible and can sometimes be bypassed. Wordfence's 'Extended Protection' feature, which includes the 'wordfence-waf.php' script, is designed to mitigate such bypass attempts. However, the ongoing scanning activity suggests that attackers are actively probing for weaknesses or misconfigurations that could allow them to circumvent these security measures.
This trend highlights the persistent cat-and-mouse game between security vendors and threat actors. Even robust security solutions like Wordfence are subject to continuous scrutiny and attempts at evasion. The observed scans serve as a reminder for website administrators to ensure their Wordfence installations are up-to-date, properly configured, and that underlying WordPress core, themes, and plugins are also patched promptly.
Administrators are advised to monitor their logs for similar scanning activity and to follow Wordfence's official guidance on optimizing their firewall settings and preventing bypasses. The presence of 'wordfence-waf.php' is a strong indicator of a site's security posture, and attackers are clearly attempting to leverage this knowledge for their own malicious purposes.