Last updated: August 19, 2026 at 1:47 AM UTC
All 741 Vulnerability 286 Breach 129 Threat 319 Defense 7
Tag: file-upload (3 articles)Clear

CISA flags two exploited Joomla extension flaws that let attackers upload web shells

CISA has added two actively exploited vulnerabilities to its Known Exploited Vulnerabilities catalog, both in popular Joomla extensions and both allowing attackers to upload dangerous files. The iCagenda event calendar flaw (CVE-2026-48939, rated 10.0) lets an attacker upload arbitrary files through its attachment feature, ending in PHP code execution, while the Balbooa Forms flaw (CVE-2026-56291) allows unauthenticated upload of executable files leading to full remote code execution. Federal agencies were ordered to fix them by July 13. The additions line up with a broader campaign, recently flagged by Australia's cyber agency, in which attackers scan the internet and exploit known content-management-system and plugin flaws to plant web shells on vulnerable sites.

Check
Identify Joomla sites using the iCagenda or Balbooa Forms extensions, update them to fixed versions, and inspect web directories for unexpected PHP files or web shells indicating a successful upload.
Affected
Websites running the iCagenda or Balbooa Forms Joomla extensions (CVE-2026-48939, CVE-2026-56291); attackers are actively uploading malicious files to gain remote code execution and plant web shells on affected servers.
Fix
Update the affected extensions to patched versions, remove unused plugins, make web directories read-only where possible, monitor for unauthorized file creation, and block unexpected child processes spawning from web servers.

Attackers actively exploiting critical unauthenticated file upload flaw in Breeze Cache WordPress plugin on 400,000 sites (CVE-2026-3844)

Wordfence has seen more than 170 live exploit attempts against CVE-2026-3844, a critical unauthenticated arbitrary file upload in the Breeze Cache WordPress plugin from Cloudways. Breeze has roughly 400,000 active installations, making this one of the larger exposure events of the month. The flaw lives in the fetch_gravatar_from_remote function, which fetches avatar images from an arbitrary remote URL and saves them locally without validating the downloaded file's MIME type - so an attacker can point it at a .php payload and drop a webshell directly into a web-accessible directory. The attack is only possible when the 'Host Files Locally - Gravatars' add-on is enabled, which is not the default, but any site that turned it on for performance reasons is wide open. Cloudways shipped the fix as Breeze 2.4.5 earlier this week; as of publication only about 138,000 of the 400,000 installations had downloaded the patched version, leaving hundreds of thousands of sites exposed to a pre-auth RCE with 9.8 CVSS.

Check
Check every WordPress installation you run or manage (including marketing microsites, staff personal sites on corporate subdomains, and legacy tenant sites) for the Breeze Cache plugin and its version.
Affected
Breeze Cache WordPress plugin versions 2.4.4 and earlier, but only when the 'Host Files Locally - Gravatars' sub-feature has been enabled. CVSS 9.8. Discovered by security researcher Hung Nguyen (bashu). If you do not run that sub-feature the plugin is not currently exploitable via this bug, but the fix should still be applied immediately.
Fix
Update Breeze Cache to version 2.4.5 immediately across every site that uses it. If you cannot update straight away, disable the 'Host Files Locally - Gravatars' option or temporarily deactivate the plugin entirely. After patching, hunt the site's wp-content/uploads/cache directory and similar writable paths for recently-created .php files and files with mismatched MIME types, check for new WordPress admin users, and review web server logs for POSTs to the Breeze gravatar endpoint from the exploitation window. Confirm no webshell has been planted before declaring the site clean.

Ninja Forms WordPress plugin allows unauthenticated file upload leading to remote code execution

A critical vulnerability in the Ninja Forms File Uploads premium add-on for WordPress allows attackers to upload arbitrary files - including PHP web shells - without any authentication. Over 800,000 WordPress sites use Ninja Forms, and the File Uploads extension is one of its most popular premium add-ons. Successful exploitation gives an attacker full code execution on the web server. No user interaction required - just a crafted request to the file upload endpoint.

Check
Check if any of your WordPress sites use the Ninja Forms File Uploads premium add-on. This is a premium extension, not the free Ninja Forms base plugin.
Affected
WordPress sites running the Ninja Forms File Uploads premium add-on (vulnerable versions not yet confirmed in public reporting). The free base Ninja Forms plugin alone is not affected.
Fix
Update the Ninja Forms File Uploads add-on to the latest version immediately. If you can't patch right away, temporarily disable the file upload functionality. Review your web server logs for unexpected file uploads in the Ninja Forms upload directory. Use a WAF rule to block PHP file uploads to Ninja Forms endpoints.