CVE-2024-21410: Microsoft Exchange Server Privilege Escalation Vulnerability
- Is it exploited?
Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 15 Feb 2024, 2 days after the CVE record was published.
- How likely is exploitation in the next 30 days?
- 12.7%
EPSS score, percentile 96.2 of all scored records
- How severe?
- 9.8 Critical
CVSS v3.1 base score, given by the CNA
- What should I do?
CISA deadline 7 Mar 2024. Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- Which versions are affected?
Affected
- from 15.01.0 to before 15.01.2507.037
- from 15.02.0 to before 15.2.1544.004
- from 15.02.0 to before 15.2.1544.004
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
What to do
Required action, set by CISA
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
CISA due date for this action: 7 March 2024.
Advisories and patches
Linked from CISA's catalog entry
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-21410
- https://nvd.nist.gov/vuln/detail/CVE-2024-21410
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | from 15.01.0 to before 15.01.2507.037 |
| Status | Versions |
|---|---|
| Affected | from 15.02.0 to before 15.2.1544.004 |
| Status | Versions |
|---|---|
| Affected | from 15.02.0 to before 15.2.1544.004 |
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
About this vulnerability
Microsoft Exchange Server contains an unspecified vulnerability that allows for privilege escalation.
Summary: CISA's KEV catalog, as of 28 Oct 2026.
- CISA added CVE-2024-21410 to its Known Exploited Vulnerabilities (KEV) catalog on 15 Feb 2024.
- CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
- The due date CISA sets for the required action is 7 Mar 2024.
- The CVE record was published on 13 Feb 2024, 2 days before it was added to KEV.
- The CVE record carries a CVSS v3.1 base score of 9.8 (Critical), given by its CNA.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 12.7% (percentile 96.2), as of 28 Oct 2026.
- CISA's SSVC assessment in the CVE record: exploitation active, automatable yes, technical impact total.
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.
Description
Microsoft Exchange Server Elevation of Privilege Vulnerability
Microsoft Exchange Server Elevation of Privilege Vulnerability
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
Weakness
- CWE-287: Improper Authentication
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.
Timeline
| Date | Event |
|---|---|
| 13 Feb 2024 | CVE record published |
| 15 Feb 2024 | Added to CISA KEV |
| 7 Mar 2024 | CISA due date for the required action |
| 10 Aug 2026 | CVE record last updated |
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