8.1
High
Exploited
CVE-2026-42897 Microsoft Exchange Server Cross-Site Scripting Vulnerability
Active exploitation observed
· CISA KEV catalogue
Required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Ransomware campaigns
Not observed so far
Weakness
CWE-79
Description
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Microsoft Exchange Server 2016 Cumulative Update 23 15.01 | 15.01.0.0 → < 15.01.2507.069 | 15.01.2507.069 |
| Microsoft Exchange Server 2019 Cumulative Update 14 15.02 | 15.02.0.0 → < 15.02.1544.041 | 15.02.1544.041 |
| Microsoft Exchange Server 2019 Cumulative Update 15 15.02 | 15.02.0.0 → < 15.02.1748.046 | 15.02.1748.046 |
| Microsoft Exchange Server Subscription Edition RTM 15.02 | 15.02.0.0 → < 15.02.2562.043 | 15.02.2562.043 |
References
- Microsoft Exchange Server Spoofing Vulnerability msrc.microsoft.com
Timeline
- Published
- Added to the KEV catalogue
- Last modified
Other CVEs of Microsoft Exchange Server 2016 Cumulative Update 23
The 88 CVEs of Microsoft Exchange Server 2016 Cumulative Update 23 →
CVE-2026-87695
Inclusion of functionality from untrusted control sphere in Microsoft Exchange Server allows an authorized attacker to…
7.8
High
CVE-2026-87692
Deserialization of untrusted data in Microsoft Exchange Server allows an authorized attacker to elevate privileges…
7.8
High
CVE-2026-70279
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows…
9.3
Critical
CVE-2026-87696
Improper verification of cryptographic signature in Microsoft Exchange Server allows an authorized attacker to elevate…
7.5
High