MSRXVulnerabilities / CVE-2026-42897
CVE-2026-42897
Published 2026-05-14 · published (not yet in NVD)
CVE-2026-42897
Microsoft Exchange Server Spoofing Vulnerability
Exploited in the wild: CISA added it to the Known Exploited Vulnerabilities catalog on 2026-05-15, with a fix-by date of 2026-05-29. Patch it first.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
8.1 HIGH
CVSS 3.1 · CNA
CVSS 3.1 · CNA
71%
chance of exploitation in the next 30 days (EPSS; in the top 1% of all CVEs)
chance of exploitation in the next 30 days (EPSS; in the top 1% of all CVEs)
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
- Microsoft Microsoft Exchange Server 2016 Cumulative Update 23: 15.01.0.0 to < 15.01.2507.069
- Microsoft Microsoft Exchange Server 2019 Cumulative Update 14: 15.02.0.0 to < 15.02.1544.041
- Microsoft Microsoft Exchange Server 2019 Cumulative Update 15: 15.02.0.0 to < 15.02.1748.046
- Microsoft Microsoft Exchange Server Subscription Edition RTM: 15.02.0.0 to < 15.02.2562.043
Weakness: CWE-79
1 references (advisories, patches, write-ups)
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42897 · vendor-advisory, patch
Sources: CVE.org, FIRST EPSS. Missing ones did not answer or have no record yet.