Threats / Microsoft / CVE-2023-24880
CVE-2023-24880
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-08-04
Microsoft Windows vulnerability
Microsoft Windows SmartScreen bypass vulnerability allows attackers to evade Mark of the Web defenses using specially crafted malicious files, enabling execution of untrusted content.
Verdict
Today item, not a backlog item.
An authorization bypass in Windows SmartScreen permits circumvention of MOTW protections designed to warn users about downloaded files. Attackers exploit this to deliver malware while bypassing security warnings, facilitating ransomware deployment and data theft campaigns.
CISA KEV Yes · 2023-03-145Ransomware use Flagged5EPSS 0.78152 (verify live)6CVSS 4.43CISA SSVC Exploitation: active · Automatable: no · Impact: partial4
01
Is it exploitable?
— the evidence, ranked above the scoreReported exploitation
11 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-03-14), flagged for known ransomware use.
Probability (EPSS)
EPSS 0.78152 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 4.4 (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L/E:F/RL:O/RC:C) · Affected: Microsoft, Windows. Confirm exact fixed builds in the vendor advisory.CVSS — CNA-assigned (CVE.org), version 3.1, set at disclosure.
Weakness (CWE)
Mapped to CWE-863 Incorrect Authorization — weakness family: Authorization / access control.CWE assignment from the public NVD record (may be stale); the weakness class drives how the flaw is exploited.
CISA SSVC (triage disposition)
Exploitation: active · Automatable: no · Technical Impact: partialCISA's own stakeholder-specific triage inputs, published in the CVE record (CISA Coordinator role). NOTE: this is CISA's three decision points; the final Act/Attend/Track decision also requires a Mission & Well-being input not published here, so no overall decision is asserted.
Currency of the record
CISA added this to its KEV catalog the same day the CVE record was published.KEV lag = CISA-KEV dateAdded − CVE.org datePublished; a floor on how long the known-exploited flaw sat in the public record before the federal catalog listed it. Severity/weakness here is CNA- or CISA-assigned (current at disclosure), independent of NVD's analysis backlog.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I craft a malicious file that bypasses SmartScreen's MOTW detection mechanisms.
Business
Security controls fail to alert users to untrusted downloaded content, increasing infection risk.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I distribute the file through email or web downloads without triggering security warnings.
Business
End users execute malware believing it is safe, enabling initial system compromise.
3
Lateral reach — past segmentation narrative 3
Attacker
I establish persistence and deploy ransomware or data exfiltration payloads across the network.
Business
Ransomware campaigns encrypt critical assets or steal sensitive data, causing operational disruption and financial loss.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05