Known exploited · Microsoft
CVE-2024-29988: Microsoft SmartScreen Prompt Security Feature Bypass Vulnerability
What it is
Microsoft SmartScreen Prompt contains a security feature bypass vulnerability that allows an attacker to bypass the Mark of the Web (MotW) feature. This vulnerability can be chained with CVE-2023-38831 and CVE-2024-21412 to execute a malicious file.
- Vendor
- Microsoft
- Product
- SmartScreen Prompt
- Added to KEV
- April 30, 2024
- CISA due date
- May 21, 2024
- Ransomware use
- Unknown
What CISA requires
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Forensic triage
No
What to do now
- Find every instance of SmartScreen Prompt you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before May 21, 2024 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.