Vulnerability in Microsoft Exchange Server 2016 Cumulative Update 23

CVE-2025-25006

Improper handling of additional special element in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network.

EPSS: 0.015 (81.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:U/RL:O/RC:C.

Affected products

Microsoft Exchange Server 2016 Cumulative Update 23 — versions 15.01.0.0
Microsoft Exchange Server 2019 Cumulative Update 14 — versions 15.02.0.0
Microsoft Exchange Server 2019 Cumulative Update 15 — versions 15.02.0.0
Microsoft Exchange Server Subscription Edition Rtm — versions 15.02.0.0

Weakness classification (CWE)

CWE-167

References

Microsoft Exchange Server Spoofing Vulnerability (vendor-advisory, patch)

Frequently asked questions

What is CVE-2025-25006?: CVE-2025-25006 is a medium-severity vulnerability in Microsoft Exchange Server 2016 Cumulative Update 23, classified under CWE-167. CVSS score: 5.3/10. Published 2025-08-12.
How severe is CVE-2025-25006?: Medium severity. CVSS v3 base score is 5.3 out of 10.