CVE-2024-21351
Windows SmartScreen Security Feature Bypass Vulnerability
- CVSS
- 7.6Highscored by the publisher (CNA)
- Exploited in the wild
- Yes, in CISA KEV since 13 Feb 2024CISA deadline for US federal agencies: 5 Mar 2024
- EPSS
- 27.8%chance of exploitation in the next 30 daystop 2% of scored CVEsFIRST score of 11 Nov 2026
- Fix
- Patch availablesee the advisories in the references
- Published
- 13 Feb 2024analysed here 12 Nov 2026
Do first. Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. (CISA's required action for this KEV entry)
Summary
Triage
- Attack surface
- Server-side
- Exploitable
- At runtime
- Attack vector
- network
- Weakness
- CWE-94 Code Injection
The summary, impact and action text on this page are written by our AI analysis pipeline, or taken from the NVD description when a CVE was imported from NVD. They are not the vendor's wording: check them against the sources. A longer AI executive summary and technical analysis are generated for signed-in accounts on the Max plan.
Affected products
| Product | Affected versions | Vendor says fixed in |
|---|---|---|
| Microsoft Windows 10 Version 1507 | >= 10.0.10240.0 and < 10.0.10240.20469Vendor says fixed in: not stated | |
| Microsoft Windows 10 Version 1607 | >= 10.0.14393.0 and < 10.0.14393.6709Vendor says fixed in: not stated | |
| Microsoft Windows 10 Version 1809 | >= 10.0.17763.0 and < 10.0.17763.5458>= 10.0.0 and < 10.0.17763.5458Vendor says fixed in: not stated | |
| Microsoft Windows 10 Version 21H2 | >= 10.0.19043.0 and < 10.0.19044.4046Vendor says fixed in: not stated | |
| Microsoft Windows 10 Version 22H2 | >= 10.0.19045.0 and < 10.0.19045.4046Vendor says fixed in: not stated | |
| Microsoft Windows 11 version 21H2 | >= 10.0.0 and < 10.0.22000.2777Vendor says fixed in: not stated | |
| Microsoft Windows 11 version 22H2 | >= 10.0.22621.0 and < 10.0.22621.3155Vendor says fixed in: not stated | |
| Microsoft Windows 11 version 22H3 | >= 10.0.22631.0 and < 10.0.22631.3155Vendor says fixed in: not stated | |
| Microsoft Windows 11 Version 23H2 | >= 10.0.22631.0 and < 10.0.22631.3155Vendor says fixed in: not stated | |
| Microsoft Windows Server 2016 | >= 10.0.14393.0 and < 10.0.14393.6709Vendor says fixed in: not stated | |
| Microsoft Windows Server 2019 | >= 10.0.17763.0 and < 10.0.17763.5458Vendor says fixed in: not stated | |
| Microsoft Windows Server 2022 | >= 10.0.20348.0 and < 10.0.20348.2322Vendor says fixed in: not stated |
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.
Products named in our analysis
- microsoft:windows_10_1507
- microsoft:windows_10_1607
- microsoft:windows_10_1809
- microsoft:windows_10_21h2
- microsoft:windows_10_22h2
- microsoft:windows_11_21h2
- microsoft:windows_11_22h2
- microsoft:windows_11_23h2
- microsoft:windows_server_2016
- microsoft:windows_server_2019
- microsoft:windows_server_2022
- microsoft:windows_server_2022_23h2
Fix and mitigation
WAF and other mitigations
Can a WAF block it? No. The vulnerability affects the Windows SmartScreen security feature, which is part of the operating system and requires local user interaction to trigger. It is not reachable via web requests. A web application firewall only sees HTTP traffic, so it is not on this attack's path.
Also consider: remove eval sinks · RASP
Based on an AI reading of the CVE description, and no vendor rule found yet. We check Cloudflare, AWS, Google Cloud Armor and Azure; for Akamai, Imperva, Fastly, F5, ask your vendor.
Remediation steps (AI-written)
Step-by-step remediation is generated for accounts on the Max plan, for CVEs that match a technology in their stack. Add this technology to your stack to see the fix checklist.
Exploitation evidence
- CISA KEV catalog
- Listed since 13 Feb 2024.
- CISA due date
- 5 Mar 2024, the remediation deadline for US federal agencies
- CISA required action
- Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- Public exploit code
- None on record in Exploit-DB, Metasploit, Nuclei templates or PoC-in-GitHub.
- CISA SSVC
- exploitation active, automatable no, technical impact partialAssessed by CISA 1 May 2024 (SSVC 2.0.3). Exploitation is none, poc (public proof of concept) or active.
Timeline
- 13 Feb 2024Added to CISA KEV (exploited in the wild)
- 13 Feb 2024Published1 day later
- 5 Mar 2024CISA remediation due date (US federal agencies)20 days later
- 1 May 2024CISA SSVC assessment: exploitation active58 days later
- 10 Aug 2026CVE record last updated831 days (about 2 years) later
- 12 Nov 2026Analysed by vulneraibility.com94 days (about 3 months) later
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:L
| Metric | Value | What it means |
|---|---|---|
| Attack vector | NetworkReachable over the internet or any routable network. | Reachable over the internet or any routable network. |
| Attack complexity | LowRepeatable attack, no special conditions. | Repeatable attack, no special conditions. |
| Privileges required | NoneThe attacker needs no prior access. | The attacker needs no prior access. |
| User interaction | RequiredA victim must click, open or otherwise cooperate. | A victim must click, open or otherwise cooperate. |
| Scope | UnchangedImpact stays within the vulnerable component. | Impact stays within the vulnerable component. |
| Confidentiality | LowPartial data disclosure. | Partial data disclosure. |
| Integrity | HighComplete modification possible. | Complete modification possible. |
| Availability | LowPartial degradation possible. | Partial degradation possible. |
Common questions
Is CVE-2024-21351 being exploited?
Yes. CVE-2024-21351 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.
How severe is CVE-2024-21351?
CVE-2024-21351 is rated High with a CVSS score of 7.6. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2024-21351?
Yes. A fix has been recorded for CVE-2024-21351. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2024-21351 affect?
CVE-2024-21351 affects microsoft:windows_10_1507, microsoft:windows_10_1607, microsoft:windows_10_1809, microsoft:windows_10_21h2, and 8 further products or versions. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
References
2 references in the CVE record, grouped by the tags the record gives them.
Patches (1)
- msrc.microsoft.com /update-guide/vulnerability/CVE-2024-21351
Other links (1)
- cisa.gov /known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-21351
Where the data on this page comes from
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- CISA KEV catalog: exploitation, date added, due date
- CISA Vulnrichment (ADP): SSVC decision points
- FIRST EPSS: exploit probability and percentile
Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.
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