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.
Australia's Cyber Security Centre has warned of a large-scale global campaign in which attackers scan websites and exploit known vulnerabilities in content management systems and their plugins to plant web shells. The affected software spans WordPress, Joomla, Craft CMS, and others, with the flaws typically allowing unauthenticated file upload, remote code execution, or server-side request forgery. Once a web shell is installed, attackers can take a site offline, deface it, steal data stored on the server, or pivot deeper into the network. Many small and medium-sized businesses have already been hit, and the agency notes the campaign may be accelerated by AI, which helps attackers scale exploitation of newly disclosed flaws.
A critical flaw in the Joomla Content Editor (JCE), one of the most widely used editor extensions for the Joomla CMS, is being actively exploited to take over websites. The bug (CVE-2026-48907, rated a perfect 10) is an access-control failure that lets an unauthenticated attacker create editor profiles and then upload and run arbitrary PHP code, leading to full server compromise. CISA added it to its known-exploited list and ordered federal agencies to patch by June 19. Working exploit code is public and attacks are automated, so even sites with no public registration are at risk. Patching closes the hole but does not remove anything attackers already planted.
Attackers compromised Nextend's update infrastructure and pushed a fully weaponized version of Smart Slider 3 Pro (3.5.1.35) through the official WordPress and Joomla update channel on April 7. Sites with auto-updates enabled received a multi-layered remote access toolkit disguised as a legitimate plugin update. The malicious version was live for approximately six hours before detection. Patchstack's analysis found: unauthenticated remote command execution via crafted HTTP headers, a second authenticated backdoor with PHP eval and OS command execution, a hidden administrator account (prefixed wpsvc_) invisible in the admin interface, persistent backdoors planted in the active theme's functions.php and wp-config.php, and automated credential theft sent to an external server. Traditional defenses like firewalls, nonce verification, and role-based access controls are irrelevant here because the malicious code arrived through the trusted update channel. Affected sites should be considered fully compromised.
TrustStrike Labs