CVE-2024-21413

Microsoft Office Outlook: Outlook Improper Input Validation

As of , CVE-2024-21413 in Microsoft Office Outlook is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch this week.

Exploited
Yes: CISA listed it on 6 February 2025
US federal deadline
27 February 202521 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Not known to CISA
EPSS score
0.95Higher than 99% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
EPSS when listed
0.00 on 6 February 2025EPSS on the day CISA listed it.
Public exploit
None foundNeither Metasploit nor Exploit-DB lists one.
Fix
Vendor advice: msrc.microsoft.comLinks below, from CISA's entry.

What CISA says to do

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

CISA's required action

What the flaw is

Microsoft Outlook contains an improper input validation vulnerability that allows for remote code execution. Successful exploitation of this vulnerability would allow an attacker to bypass the Office Protected View and open in editing mode rather than protected mode.

CISA's description

Microsoft Outlook Remote Code Execution Vulnerability

The CVE record's description, from microsoft

CVE published
13 February 2024
Assigned by
microsoft
CVSS
9.8 Critical (CVSS 3.1, from the CNA)
CWE-20
Improper Input Validation
CISA SSVC, exploitation
active
CISA SSVC, automatable
yes
CISA SSVC, technical impact
total

Timeline

  1. The CVE record was published.
  2. CISA added it to its list of exploited vulnerabilities.
  3. The US federal deadline to fix it.

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