A critical security flaw has been disclosed in a popular WordPress plugin called Ultimate Member that has more than 200,000 active installations.

The vulnerability, tracked as CVE-2024-1071, carries a CVSS score of 9.8 out of a maximum of 10. Security researcher Christiaan Swiers has been credited with discovering and reporting the flaw.

In an advisory published last week, WordPress security company Wordfence said the plugin is "vulnerable to SQL Injection via the 'sorting' parameter in versions 2.1.3 to 2.8.2 due to insufficient escaping on the user supplied parameter and lack of sufficient preparation on the existing SQL query."

As a result, unauthenticated attackers could take advantage of the flaw to append additional SQL queries into already existing queries and extract sensitive data from the database.

It's worth noting that the issue only affects users who have checked the "Enable custom table for usermeta" option in the plugin settings.

Following responsible disclosure on January 30, 2024, a fix for the flaw has been made available by the plugin developers with the release of version 2.8.3 on February 19.

Users are advised to update the plugin to the latest version as soon as possible to mitigate potential threats, especially in light of the fact that Wordfence has already blocked one attack attempting to exploit the flaw over the past 24 hours.

In July 2023, another shortcoming in the same plugin (CVE-2023-3460, CVSS score: 9.8) was actively exploited by threat actors to create rogue admin users and seize control of vulnerable sites.

The development comes amid a surge in a new campaign that leverages compromised WordPress sites to inject crypto drainers such as Angel Drainer directly or redirect site visitors to Web3 phishing sites that contain drainers.

"These attacks leverage phishing tactics and malicious injections to exploit the Web3 ecosystem's reliance on direct wallet interactions, presenting a significant risk to both website owners and the safety of user assets," Sucuri researcher Denis Sinegubko said.

It also follows the discovery of a new drainer-as-a-service (DaaS) scheme called CG (short for CryptoGrab) that runs a 10,000-member-strong affiliate program comprised of Russian, English, and Chinese speakers.

One of the threats actor-controlled Telegram channels "refers attackers to a telegram bot that enables them to run their fraud operations without any third-party dependencies," Cyfirma said in a report late last month.

"The bot allows a user to get a domain for free, clone an existing template for the new domain, set the wallet address where the scammed funds are supposed to be sent, and also provides Cloudflare protection for that new domain."

The threat group has also been observed using two custom telegram bots called SiteCloner and CloudflarePage to clone an existing, legitimate website and add Cloudflare protection to it, respectively. These pages are then distributed mostly using compromised X (formerly Twitter) accounts.