Microsoft Exchange Server cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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6.1$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Microsoft Exchange Server. This affects an unknown function. Such manipulation leads to cross site scripting. This vulnerability is uniquely identified as CVE-2026-42897. The attack can be launched remotely. Moreover, an exploit is present.

Detailsinfo

A vulnerability was found in Microsoft Exchange Server (affected version not known). It has been rated as problematic. Affected by this issue is some unknown functionality. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. CVE summarizes:

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.

The advisory is shared for download at msrc.microsoft.com. This vulnerability is handled as CVE-2026-42897 since 05/01/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. Technical details are unknown but an exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 05/22/2026). The MITRE ATT&CK project declares the attack technique as T1059.007.

It is declared as attacked. The vulnerability scanner Nessus provides a plugin with the ID 316010 (Security Updates for Microsoft Exchange Server (May 2026)), which helps to determine the existence of the flaw in a target environment. This issue was added on 05/15/2026 to the CISA Known Exploited Vulnerabilities Catalog with a due date of 05/29/2026:

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

The vulnerability is also documented in the databases at Zero-Day.cz (1098), Tenable (316010) and CERT Bund (WID-SEC-2026-1536). Once again VulDB remains the best source for vulnerability data.

Affected

  • Microsoft Exchange

Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.2
VulDB Meta Temp Score: 6.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 6.1
NVD Vector: 🔒

CNA Base Score: 8.1
CNA Vector (microsoft): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Attacked

EPSS Score: 🔒
EPSS Percentile: 🔒

KEV Added: 🔒
KEV Due: 🔒
KEV Remediation: 🔒
KEV Ransomware: 🔒
KEV Notice: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 316010
Nessus Name: Security Updates for Microsoft Exchange Server (May 2026)

Zero-Day.cz: 🔒

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

05/01/2026 CVE reserved
05/14/2026 +13 days Advisory disclosed
05/14/2026 +0 days VulDB entry created
05/22/2026 +8 days VulDB entry last update

Sourcesinfo

Vendor: microsoft.com

Advisory: msrc.microsoft.com
Status: Confirmed

CVE: CVE-2026-42897 (🔒)
GCVE (CVE): GCVE-0-2026-42897
GCVE (VulDB): GCVE-100-363932
CERT Bund: WID-SEC-2026-1536 - Microsoft Exchange Server: Schwachstelle ermöglicht Cross-Site-Scripting- und Spoofing-Angriffe

scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 05/14/2026 20:02
Updated: 05/22/2026 22:31
Changes: 05/14/2026 20:02 (61), 05/15/2026 19:43 (13), 05/17/2026 10:23 (7), 05/19/2026 11:14 (9), 05/22/2026 04:43 (2), 05/22/2026 22:31 (2)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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