high Known exploitedREV. 01

CVE-2024-21351Windows — the reputation prompt talked into silence

A crafted file gets past the reputation prompt (SmartScreen) and injects code, which Microsoft says can end in code execution, exposed data, a machine that stops responding, or all three. No further detail is published.

YOUR NEXT MOVE

Install the February 2024 Windows update, and treat a file that opened without any warning as unvetted — the warning is precisely what this flaw removes.

Read the risk

THE VITAL STATS
CVSS score
7.6/ 10
CVSS v3.1
EPSS probability
30%
Likelihood of exploitation
Attack complexity
Low
Conditions needed to exploit
Known exploited
Yes — CISA KEV
CVE published
2024-02-13
Added to KEV
2024-02-13
Exploit published
Not recorded
Confidence
medium
Kill chain
defense evasion
MITRE ATT&CK
T1553.005
Severity
high

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:L

Attacker needsThe user must open a file the attacker delivered.

Behind the card

3 REFERENCES
Field-level provenanceTRACE THE SOURCES +

Which source supports each field, when it was retrieved, and who extracted it.

FieldsSourceRetrievedExtractorConfidence
cvss, exploitation.attack_complexity, exploitation.exploit_available, references, published_atnvd.nist.gov2026-09-24scrty-crds-pipeline/0.1high
exploitation.known_exploited, exploitation.kev_addedcisa.gov2026-09-24scrty-crds-pipeline/0.1high
epssapi.first.org2026-09-24scrty-crds-pipeline/0.1high
title, summary, severity, remediation, mitre_attack, kill_chain, recommended_action, confidence, tags, exploitation.prerequisitesnvd.nist.gov2026-09-24claude-codehigh

Printing history

THE RECORD
  1. r1Initial base card

First printing. This card has not been reprinted since publication.

crds:cve-2024-21351 · CRDS 0.1 · Issued 2026-09-24