CISA Adds Six Exploited Flaws to KEV, Including NetScaler, Linux, and SQL Server Bugs
CISA added six actively exploited flaws to KEV, led by Citrix NetScaler CVE-2026-8452, with federal patch deadlines set.
CISA added six flaws to the KEV catalog on August 27, 2026, citing evidence of active exploitation, led by CVE-2026-8452, an improper buffer restriction in Citrix NetScaler ADC and Gateway that can cause denial-of-service. Defused Cyber and Previdian reported active exploitation of CVE-2026-8452, with 36 attempts over 12 days from 12 attacker IPs deploying web shells x.php and z.php. The other additions cover SQL Server RCE (CVE-2019-1068), Linux kernel out-of-bounds write (CVE-2022-0995), Red Hat ABRT and libuser privilege escalations (CVE-2015-5287, CVE-2015-3246), and AjaxPro deserialization RCE (CVE-2021-23758). FCEB agencies must patch CVE-2019-1068 and CVE-2026-8452 by August 29, 2026, and the rest by September 9, 2026.
GeoServer Zero-Day Targeted in Active Exploitation Attempts, Can Lead to RCE
A CVSS 9.8 SQL injection zero-day in GeoServer's PostGIS datastore enables RCE and drew active exploitation; fixes shipped in versions 3.0.1, 2.28.5, 2.27.6.
A SQL injection flaw in GeoServer's jsonArrayContains function within the GeoTools PostGIS datastore (GHSA-mqjf-5f49-2fjh, CVSS 9.8) was disclosed August 12, 2026, and saw hundreds of exploitation attempts within hours per watchTowr. An attacker-controlled value is interpolated into a PostgreSQL jsonb_path_exists() expression without escaping; with superuser or pg_execute_server_program privileges it escalates to OS command execution via WFS 1.0. GeoServer released versions 3.0.1, 2.28.5, and 2.27.6, and the flaw is a regression of CVE-2023-25158. GeoServer has a history of mass exploitation, including CVE-2024-36401 used for botnets and proxies.
ShieldBreak: New Windows Zero-Day Bypasses Microsoft’s RoguePlanet Patch
Researcher Chaotic Eclipse published a PoC bypassing Microsoft's CVE-2026-50656 Defender patch, enabling SYSTEM-level code execution on fully patched Windows systems.
Security researcher Chaotic Eclipse released a proof-of-concept for ShieldBreak, a Microsoft Defender zero-day that fully bypasses the patch for CVE-2026-50656 (RoguePlanet), a race condition in the Malware Protection Engine (mpengine.dll) allowing SYSTEM-level code execution. The PoC was tested on Windows 11 25H2 and Windows Server 2025 with a 100% success rate, and Windows 10 is also vulnerable though not supported by the PoC; the flaw may also leak 8 bytes of memory. Microsoft's MSRC had criticized the researcher's repeated uncoordinated disclosures, including YellowKey (BitLocker bypass), GreenPlasma, and LegacyHive (User Profile Service LPE).