CVE-2026-42897CISA KEV

Microsoft Exchange Server Cross-Site Scripting Vulnerability

Severity unknownCVSS unknownCheck the vendor advisory for fixed versions

CISA lists this Microsoft vulnerability as known exploited. Its MSRC release detail is outside this installation's collected history.

CISA KEV Check MSRC

CISA catalog record

Microsoft Exchange Server contains a cross-site scripting vulnerability during web page generation in Outlook Web Access and when certain interaction conditions are met, arbitrary JavaScript can be executed in the browser context.

Product: Microsoft
Added to KEV: 15 May 2026
Federal remediation due: 29 May 2026
Known ransomware use: Not reported

Page history

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Field-level log (2)

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23 Oct 2026 · 09:33:49 UTC Source coverage: cisa-kevIncomplete → Current
23 Oct 2026 · 08:31:50 UTC Source coverage: cisa-kevCurrent → Incomplete

Explore global source statements, affected packages and advisory history for CVE-2026-42897. The catalog has a separate collection scope from Microsoft release records.

More advisories, affected versions and source history

cve-program · CVE-2026-42897

Published

Microsoft Exchange Server 2016 Cumulative Update 23

Vendor product

Publisher's version information

Shown as published. These rules are not interpreted as NuGet package version ranges.

{
                    "vendor": "Microsoft",
                    "product": "Microsoft Exchange Server 2016 Cumulative Update 23",
                    "platforms": [
                        "x64-based Systems"
                    ],
                    "versions": [
                        {
                            "version": "15.01.0.0",
                            "lessThan": "15.01.2507.069",
                            "versionType": "custom",
                            "status": "affected"
                        }
                    ]
                }

Microsoft Exchange Server 2019 Cumulative Update 14

Vendor product

Publisher's version information

Shown as published. These rules are not interpreted as NuGet package version ranges.

{
                    "vendor": "Microsoft",
                    "product": "Microsoft Exchange Server 2019 Cumulative Update 14",
                    "platforms": [
                        "x64-based Systems"
                    ],
                    "versions": [
                        {
                            "version": "15.02.0.0",
                            "lessThan": "15.02.1544.041",
                            "versionType": "custom",
                            "status": "affected"
                        }
                    ]
                }

Microsoft Exchange Server 2019 Cumulative Update 15

Vendor product

Publisher's version information

Shown as published. These rules are not interpreted as NuGet package version ranges.

{
                    "vendor": "Microsoft",
                    "product": "Microsoft Exchange Server 2019 Cumulative Update 15",
                    "platforms": [
                        "x64-based Systems"
                    ],
                    "versions": [
                        {
                            "version": "15.02.0.0",
                            "lessThan": "15.02.1748.046",
                            "versionType": "custom",
                            "status": "affected"
                        }
                    ]
                }

Microsoft Exchange Server Subscription Edition RTM

Vendor product

Publisher's version information

Shown as published. These rules are not interpreted as NuGet package version ranges.

{
                    "vendor": "Microsoft",
                    "product": "Microsoft Exchange Server Subscription Edition RTM",
                    "platforms": [
                        "x64-based Systems"
                    ],
                    "versions": [
                        {
                            "version": "15.02.0.0",
                            "lessThan": "15.02.2562.043",
                            "versionType": "custom",
                            "status": "affected"
                        }
                    ]
                }

Original source record · Cite this exact observation · Complete original publisher JSON