Threats / Microsoft / CVE-2024-21413
CVE-2024-21413
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
Microsoft Office Outlook vulnerability
Microsoft Outlook contains an improper input validation vulnerability (CWE-20) enabling remote code execution by bypassing Protected View, allowing attackers to execute code in editing mode.
Verdict
Today item — known-exploited.
An attacker can craft a malicious Office document that, when opened in Outlook, bypasses Protected View protections and executes arbitrary code with user privileges. Active exploitation in the wild demonstrates immediate risk.
01
Is it exploitable?
— the evidence, ranked above the scoreExploit available
Fully weaponized — public exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
5 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 2025-02-06).
Probability (EPSS)
EPSS 0.9466 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Microsoft, Office Outlook. Confirm exact fixed builds in the vendor advisory.
Weakness (CWE)
Mapped to CWE-20 Improper Input Validation.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
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 Office document with improper input that evades validation checks.
Business
Attackers gain initial code execution capability on user endpoints without user awareness of the risk.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I deliver the document via email attachment, relying on Outlook to open it in editing mode instead of Protected View.
Business
Email remains a primary attack vector; users cannot rely on Outlook's safety mechanisms to prevent execution.
3
Lateral reach — past segmentation narrative 3
Attacker
I execute arbitrary code with the privileges of the Outlook process and logged-in user.
Business
Compromised user accounts enable lateral movement, data exfiltration, and persistent network access.
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