---
title: "CVE-2026-42897: Microsoft Exchange Server Spoofing… | CubePath"
description: "Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows an unauthorized attacker…"
language: en
source: https://cubepath.com/security/cve/CVE-2026-42897
---

# CVE-2026-42897: Microsoft Exchange Server Spoofing… | CubePath

## 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.

Official description from the CVE record, published by microsoft. Copyright © 1999-2026 The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CVE license. [View the record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-42897)

## Key data

### CVSS 3.1 High 8.1

Score published by microsoft in the CVE record.

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

| Metric                 | Value     | What it means                                                                       |
| ---------------------- | --------- | ----------------------------------------------------------------------------------- |
| Attack vector          | Network   | The vulnerable component can be reached over a network, possibly from the Internet. |
| Attack complexity      | Low       | No special conditions are needed. The attack can be repeated at will.               |
| Privileges required    | None      | No account or privileges are needed.                                                |
| User interaction       | Required  | A user has to do something first, such as opening a file or following a link.       |
| Scope                  | Unchanged | The impact stays within the vulnerable component.                                   |
| Confidentiality impact | High      | Serious or total effect on the secrecy of data.                                     |
| Integrity impact       | High      | Serious or total effect on the trustworthiness of data.                             |
| Availability impact    | None      | No effect on availability.                                                          |

CVSS is owned and managed by FIRST.Org, Inc. (FIRST) and is used by permission. Each CVSS score on this site is shown together with its vector string, as published in the CVE record by the source named next to it. Learn more at [first.org/cvss](https://www.first.org/cvss/) .

### EPSS

Exploit Prediction Scoring System by FIRST: an estimate of the probability that exploitation activity will be observed in the next 30 days.

Score

0.70662 (70.7% probability)

Percentile

99.4%

Scores of

Nov 10, 2026

Model

v2026.06.15

### CISA Known Exploited Vulnerabilities

This CVE is listed in the CISA KEV catalog.

Name in the catalog

Microsoft Exchange Server Cross-Site Scripting Vulnerability

Added to the catalog

May 15, 2026

Federal due date

May 29, 2026

### CISA assessment as of May 14, 2026

Stakeholder-Specific Vulnerability Categorization (SSVC) decision points added by CISA.

Exploitation

Recorded by CISA as active

Automatable

no

Technical impact

total

### Weakness (CWE)

CWE catalog version 5.0.

CWE names: Copyright © 2006-2026, The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CWE license.

- [CWE-79](https://cwe.mitre.org/data/definitions/79.html) Improper Neutralization of Input During Web Page Generation

## Affected products

Products listed in the CVE record, as the CNA published them.

- Microsoft Exchange Server 2016 Cumulative Update 23

  - affected: 15.01.0.0 up to before 15.01.2507.069
- Microsoft Exchange Server 2019 Cumulative Update 14

  - affected: 15.02.0.0 up to before 15.02.1544.041
- Microsoft Exchange Server 2019 Cumulative Update 15

  - affected: 15.02.0.0 up to before 15.02.1748.046
- Microsoft Exchange Server Subscription Edition RTM

  - affected: 15.02.0.0 up to before 15.02.2562.043

## References

Links listed in the CVE record. They lead to other sites, which CubePath does not control.

- [Microsoft Exchange Server Spoofing Vulnerability](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42897)  (msrc.microsoft.com) vendor-advisory patch

## Timeline

1. ID reserved Apr 30, 2026
2. Record published May 14, 2026
3. Added to CISA KEV May 15, 2026
4. Record last updated Aug 10, 2026

## Look up another CVE

## About CubePath

CubePath is a cloud provider with data centers in Europe and the United States. It offers VPS, bare metal servers and DDoS protection.

[Cloud VPS](https://cubepath.com/vps) [DDoS protection](https://cubepath.com/ddos-protection)

Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 19:10 UTC. [Sources and licenses](https://cubepath.com/security/cve/legal)