How severe is CVE-2024-21410?

CVE-2024-21410 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2024-21410 being actively exploited?

Yes. CVE-2024-21410 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2024-02-15, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2024-21410?

CVE-2024-21410 primarily affects Microsoft Exchange Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2024-21410?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2024-21410 have an EU (EUVD) identifier?

Yes. CVE-2024-21410 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-19119. It is also flagged as exploited in the EUVD (since 2024-02-15).

When was CVE-2024-21410 published?

CVE-2024-21410 was published on 2024-02-13 and last updated on 2026-06-17.

CVE-2024-21410

CVE-2024-21410 is a critical-severity vulnerability in Microsoft Exchange Server with a CVSS 3.x base score of 9.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2024-02-15). The underlying weakness is classified as CWE-287.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 13% (96th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2024-02-15)
EU (EUVD) id: EUVD-2024-19119
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2024-02-15)
Weakness: CWE-287
Affected product: Microsoft Exchange Server
Published: 2024-02-13
Last modified: 2026-06-17

Description

Microsoft Exchange Server Elevation of Privilege Vulnerability

Frequently asked questions

What is CVE-2024-21410?: Microsoft Exchange Server Elevation of Privilege Vulnerability
How severe is CVE-2024-21410?: CVE-2024-21410 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2024-21410 being actively exploited?: Yes. CVE-2024-21410 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2024-02-15, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2024-21410?: CVE-2024-21410 primarily affects Microsoft Exchange Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-21410?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2024-21410 have an EU (EUVD) identifier?: Yes. CVE-2024-21410 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-19119. It is also flagged as exploited in the EUVD (since 2024-02-15).
When was CVE-2024-21410 published?: CVE-2024-21410 was published on 2024-02-13 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_23:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_13:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_14:*:*:*:*:*:*

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