CVE-2024-21351: Microsoft Windows SmartScreen Security Feature Bypass Vulnerability
Actively exploited. At least one CVE in this advisory is listed in the CISA Known Exploited Vulnerabilities catalog — exploitation has been observed in the wild. Treat remediation as urgent.
Microsoft Windows SmartScreen contains a security feature bypass vulnerability that allows an attacker to bypass the SmartScreen user experience and inject code to potentially gain code execution, which could lead to some data exposure, lack of system availability, or both.
CSIRTS triage
- What
- A security feature bypass vulnerability allows an attacker to inject code potentially leading to data exposure or lack of system availability.
- Who is affected
- Users of Microsoft Windows with SmartScreen enabled are affected.
- Urgency
- Remediation is urgent due to active exploitation and critical severity.
- Action
- Install the latest updates for Windows to address this vulnerability.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2024-21351
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Exploitation confirmedCVE-2024-21351Already exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 98% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2024-21351 | coverage & exploitation status | NVD · CVE.org |
Recent advisories for Microsoft Windows SmartScreen
A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.
- criticalexploitedCVE-2024-38213: Microsoft Windows SmartScreen Security Feature Bypass Vulnerabilitycisa-kev · 2024-08-13
- criticalexploitedCVE-2023-36025: Microsoft Windows SmartScreen Security Feature Bypass Vulnerabilitycisa-kev · 2023-11-14
- criticalexploitedCVE-2023-32049: Microsoft Windows Defender SmartScreen Security Feature Bypass Vulnerabilitycisa-kev · 2023-07-11
- criticalexploitedCVE-2023-24880: Microsoft Windows SmartScreen Security Feature Bypass Vulnerabilitycisa-kev · 2023-03-14
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