CVE-2022-44698

CVE-2022-44698 is a security feature bypass in Microsoft Defender SmartScreen in which specially crafted files do not properly trigger the SmartScreen Mark-of-the-Web warning prompt. The flaw is triggered over the network but requires user interaction: an attacker typically delivers a crafted file via a malicious link or phishing email, and when the user clicks or opens it, SmartScreen fails to show its usual warning. An attacker gains the ability to run malicious content on a user's machine without the standard SmartScreen prompt, making the flaw an effective delivery and initial-access aid — it has documented use in ransomware campaigns. Anyone running the affected Windows releases is exposed: Windows 10 versions 1607 through 22H2, Windows 11 21H2, and Windows Server 2016, 2019, and 2022. The vulnerability was exploited as a zero-day before patching, was added to CISA's Known Exploited Vulnerabilities catalog on 2022-12-13 with known ransomware use, and Google reported a ransomware gang abusing it in the wild.

What to do: Apply Microsoft's December 2022 security updates (or any later cumulative updates) for Windows 10, Windows 11, and Windows Server, prioritizing user workstations and systems exposed to phishing or web downloads, per the CISA KEV required action. Until patched, reinforce user awareness that downloaded files may not trigger the usual SmartScreen warning, and consider restricting download or execution of risky file types. Confirm remediation against CISA KEV guidance and treat this as high-priority given known ransomware exploitation.