Vulnerability details
CVE-2026-42897
Actively exploited
Microsoft Exchange Server
Microsoft Exchange Server Spoofing Vulnerability
CVSS 3.1
8.1High
Official 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.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 8.1High | 3.1 | CVEProject cvelistV5 (CNA) (microsoft) | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N/E:F/RL:O/RC:C |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 23 | 15.01.0.0 ≤ v < 15.01.2507.069 | CVEProject cvelistV5 (CNA) |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 14 | 15.02.0.0 ≤ v < 15.02.1544.041 | CVEProject cvelistV5 (CNA) |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 15 | 15.02.0.0 ≤ v < 15.02.1748.046 | CVEProject cvelistV5 (CNA) |
| Microsoft | Microsoft Exchange Server Subscription Edition RTM | 15.02.0.0 ≤ v < 15.02.2562.043 | CVEProject cvelistV5 (CNA) |
References and advisories
2- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42897 vendor-advisorypatch
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-42897 government-resource
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Details
- Published
- 2026-05-14
- Last updated
- 2026-08-10
- State
- Published
- Assigner (CNA)
- microsoft
- Kolun priority
- 87 · Critical
CISA KEV catalog
- Date added
- 2026-05-15
- Due date
- 2026-05-29
- Used in ransomware
- Unknown
Exploit prediction (EPSS)
70.66%
Probability of exploitation in 30 days
99.3%
Percentile (among all CVEs)
SSVC assessment (CISA)
- Automatable
- No
- Exploitation
- Active
- Technical impact
- Total
Weaknesses (CWE)
- CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')