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Search: “Malwarebytes for Windows”

22 items

Rogue ScreenConnect Installations Across Unrelated Hosts Suggest Worm-Like Activity

Huntress observed rogue ScreenConnect deployments with worm-like VBScript propagation across unrelated organizations, prompting a ConnectWise advisory on file transfer behavior.

Huntress identified multiple incidents in late August 2026 where social engineering led to rogue ScreenConnect remote access clients deployed on victim machines, which then spawned wscript.exe to run four VBScript payloads (1.vbs through 4.vbs) for profiling, telemetry collection, and persistence via a WindowsServiceHost Run key. Modified ScreenConnect clients propagated the VBScript chain to connected endpoints, creating worm-like spread. ConnectWise published an advisory on September 3, 2026, confirming an issue affecting file transfer behavior in both cloud and on-premises ScreenConnect deployments, with a CVE and fix expected within the week; partners were advised to review and disable TransferFiles permissions in the interim.

Huntress · 13d agoExploit / PoC in the wild1

Microsoft fixes record 964 flaws, including 2 exploited zero-days

Microsoft's September Patch Tuesday fixes a record 964 CVEs, including two actively exploited Windows privilege-escalation zero-days, CVE-2026-81963 and CVE-2026-85880.

Microsoft's September 2026 Patch Tuesday addresses 964 customer-patchable CVEs (104 Critical, 860 Important), the largest release on record, out of 974 total listed. Two actively exploited zero-days are fixed: CVE-2026-81963, a link-following elevation-of-privilege flaw in the Windows Update Stack, and CVE-2026-85880, a Windows ALPC heap overflow enabling AppContainer sandbox escape, both with CVSS 7.8. Both zero-days were exploited before a patch was available and grant SYSTEM-level access after an initial foothold. The release also includes high-severity RCE fixes for Windows DNS Server, Remote Desktop Services, Exchange Server, SharePoint, and SQL Server.

Malwarebytes Labs · 7d agoExploit / PoC in the wildCVE-2026-81963CVE-2026-858801

BlueMoon exploit kit turns Chrome and Windows flaws into attacks

Proofpoint documents BlueMoon exploit kit used by four espionage groups to chain Chrome V8 and Windows flaws via phishing, all now in CISA's KEV.

Proofpoint identified a shared Chrome and Windows exploit kit, BlueMoon, used by four espionage groups against Chrome on Windows within days of one another. Attacks began with phishing emails leading to web pages that exploited two Chrome V8 vulnerabilities, followed by a Windows flaw to escape browser protections and gain higher privileges. The Chrome flaws were patched in Stable on September 3 and 8, 2026, the Windows flaw was fixed in September Patch Tuesday, and all three were actively exploited and added to CISA's KEV catalog. Researchers found clues, but no conclusive evidence, that the kit was developed with AI assistance.

Malwarebytes Labsupdated · 1h agofirst · 6d agoExploit / PoC in the wild 22 sources1

Two critical Chrome flaws put users at risk on malicious websites

Google patched 26 Chrome flaws, including two critical use-after-frees and an actively exploited V8 sandbox escape (CVE-2026-85046); update to 152.0.7977.82/.83.

Chrome's desktop update fixes 26 security issues, including critical use-after-free flaws CVE-2026-84353 in Shared Tab Groups and CVE-2026-84352 in WebGL, both allowing code execution outside the browser sandbox via crafted HTML pages. Google subsequently patched CVE-2026-85046, a high-severity V8 JavaScript engine flaw with exploits already in the wild that enables arbitrary code execution inside the Chrome sandbox; HKCERT rates the overall risk as extremely high. Fixed versions are 152.0.7977.82/.83 on Windows and Mac and 152.0.7977.82 on Linux.

Update Chrome now to protect against an actively exploited vulnerability

Google shipped Chrome 153.0.8010.36/.37 fixing 230 flaws including actively exploited V8 out-of-bounds write CVE-2026-87491 enabling sandboxed code execution.

Chrome stable channel updated to 153.0.8010.36/.37 for Windows and Mac and 153.0.8010.36 for Linux, including 230 security fixes. CVE-2026-87491 is an out-of-bounds write in Chrome's V8 JavaScript engine that a crafted HTML page can exploit to execute arbitrary code inside the browser sandbox; Google rates it medium severity, but it is confirmed as actively exploited. The update also fixes five Critical vulnerabilities, four of which were found in WebGL. Users should update via Settings > About Chrome and restart the browser.

Malwarebytes Labs · 6d agoExploit / PoC in the wild 2 sourcesCVE-2026-874911