Some attackers are increasingly moving away from simple redirects in favor of more “selective” methods of payload delivery. This approach filters out regular human visitors, allowing attackers to serve malicious content to search engine crawlers while remaining invisible to the website owner. What did we find? During a malware investigation, we identified a selective content […]
Tag Archives: Malware
Google Sees Spam, You See Your Site: A Cloaked SEO Spam Attack
We recently handled a case where a customer reported strange SEO behavior on their website. Regular visitors saw a normal site. No popups. No redirects. No visible spam. However, when they checked their site on Google, the search results were flooded with eBay-type-looking websites and “Situs Toto” gambling spam. This is a professional-grade SEO cloaking […]
Fake Browser Updates Targeting WordPress Administrators via Malicious Plugin
We recently investigated a case involving a WordPress website where a customer reported persistent fake pop-up notifications appearing on their site. The warnings were urging them to update their browser (Chrome or Firefox), even though their software was already fully up-to-date. What made this case particularly unique was the targeting. The fake alerts were not […]
Slot Gacor: The Rise of Online Casino Spam
Online casino spam has been without a doubt one of the most prevalent types of spam content that we’ve seen on infected websites in recent years. An extremely common method of promoting low-quality or otherwise undesirable websites is for spammers to hack websites and fill them full of backlinks to pump their SEO. Historically this […]
Malvertising Campaign Hides in Plain Sight on WordPress Websites
Recently, one of our customers noticed suspicious JavaScript loading across their WordPress website. Visitors were being served third-party scripts that the site owner never installed. After investigation, we discovered the infection originated from a malicious modification in the active theme’s functions.php file. This injected PHP code silently fetched external JavaScript from attacker-controlled domains and inserted […]
Hidden WordPress Backdoors Creating Admin Accounts
During a recent cleanup of a compromised WordPress website, we discovered two different malicious files designed to silently manipulate administrator accounts. Attackers often inject such backdoors to maintain persistent access to a site, even if their other malware is detected and removed. These files were disguised to look like regular WordPress components, but their functionality […]
Malicious JavaScript Injects Fullscreen Iframe On a WordPress Website
Last month, we came across an ongoing JavaScript-based malware campaign affecting compromised websites. The malware injects a fullscreen iframe that silently loads content from a suspicious external domain. This type of malicious script aims to force users to view unsolicited content, often for ad fraud, traffic generation, or deceptive social engineering. This is the fake […]
Unauthorized Admin User Created via Disguised WordPress Plugin
Recently at Sucuri, we investigated a malware case reported by one of our clients. Their WordPress site was compromised, and the attacker had installed a fake plugin. Upon analysis revealed that it was a sophisticated backdoor plugin designed to create a persistent and hidden administrator account. What Did We Find? The infection was located inside […]
Uncovering a Stealthy WordPress Backdoor in mu-plugins
Recently, our team uncovered a particularly sneaky piece of malware tucked away in a place many WordPress users don’t even know exists: the mu-plugins folder. In fact, back in March, we saw a similar trend with hidden malware in this very directory, as detailed in our post Hidden Malware Strikes Again: MU-Plugins Under Attack. This […]
WordPress Redirect Malware Hidden in Google Tag Manager Code
Last month, a customer contacted us after noticing their WordPress website was unexpectedly redirecting to a spam domain. The redirection occurred approximately 4-5 seconds after a user landed on the site. Upon closer inspection of the site’s source code we found a suspicious Google Tag Manager loading. This isn’t the first time we’ve seen GTM […]
