NCSC-2026-0419

Vulnerability from csaf_ncscnl - Published: 2026-10-13 18:28 - Updated: 2026-10-13 18:28
Summary
Kwetsbaarheden verholpen in Microsoft Excange Server
Notes
The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this page to enhance access to its information and security advisories. The use of this security advisory is subject to the following terms and conditions: NCSC-NL makes every reasonable effort to ensure that the content of this page is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or continuous keeping up-to-date. The information contained in this security advisory is intended solely for the purpose of providing general information to professional users. No rights can be derived from the information provided therein. NCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of this security advisory. This includes damage resulting from the inaccuracy of incompleteness of the information contained in the advisory. This security advisory is subject to Dutch law. All disputes related to or arising from the use of this advisory will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings.
Feiten: Microsoft heeft kwetsbaarheden verholpen in Exchange.
Interpretaties: Een kwaadwillende kan de kwetsbaarheden misbruiken om zich voor te doen als andere gebruiker, zich verhoogde rechten toe te kennen en willekeurige code uit te voeren met rechten van het proces. Van de kwetsbaarheid met kenmerk CVE-2026-96940 is eerder al een out-of-band update verschenen, maar is ook opgenomen in deze cumulatieve update.
Oplossingen: Microsoft heeft updates beschikbaar gesteld waarmee de beschreven kwetsbaarheden worden verholpen. We raden u aan om deze updates te installeren. Meer informatie over de kwetsbaarheden, de installatie van de updates en eventuele work-arounds vindt u op: https://portal.msrc.microsoft.com/en-us/security-guidance
Kans: medium
Schade: high
CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-121: Stack-based Buffer Overflow
CWE-347: Improper Verification of Cryptographic Signature
CWE-502: Deserialization of Untrusted Data
CWE-829: Inclusion of Functionality from Untrusted Control Sphere
CWE-863: Incorrect Authorization
CWE-1390: Weak Authentication
CVE-2026-70279

Microsoft Exchange Server contains a cross-site scripting vulnerability caused by improper input neutralization, allowing unauthorized attackers to conduct network spoofing attacks.

Affected products
Product Identifier Version Remediation
vers:unknown/*
Microsoft / Exchange
 vers:unknown/*
vers:unknown/*
Microsoft / Microsoft Exchange Server 2016 Cumulative Update 23
 vers:unknown/*
vers:unknown/*
Microsoft / Microsoft Exchange Server 2019 Cumulative Update 14
 vers:unknown/*
vers:unknown/*
Microsoft / Microsoft Exchange Server 2019 Cumulative Update 15
 vers:unknown/*
vers:unknown/*
Microsoft / Microsoft Exchange Server Subscription Edition RTM
 vers:unknown/*
CVE-2026-70571
Affected products
Known affected 5 products, the same list as for CVE-2026-70279
CVE-2026-77910

An authorization flaw in Microsoft Exchange Server allows an authenticated attacker to remotely escalate privileges over a network, potentially compromising system integrity.

Affected products
Known affected 5 products, the same list as for CVE-2026-70279
CVE-2026-87692
Affected products
Known affected 5 products, the same list as for CVE-2026-70279
CVE-2026-87695
Affected products
Known affected 5 products, the same list as for CVE-2026-70279
CVE-2026-87696
Affected products
Known affected 5 products, the same list as for CVE-2026-70279
CVE-2026-96940

An elevation of privilege vulnerability in Microsoft Exchange Outlook Web Access (OWA) enables script/content injection via malicious links, mitigated by a security update enhancing web request validation.

8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE-1390 - Weak Authentication
Affected products
Known affected 5 products, the same list as for CVE-2026-70279
References
To clipboard 

{
  "document": {
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "distribution": {
      "tlp": {
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    "lang": "nl",
    "notes": [
      {
        "category": "legal_disclaimer",
        "text": "The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this page to enhance access to its information and security advisories. The use of this security advisory is subject to the following terms and conditions:\n\n    NCSC-NL makes every reasonable effort to ensure that the content of this page is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or continuous keeping up-to-date. The information contained in this security advisory is intended solely for the purpose of providing general information to professional users. No rights can be derived from the information provided therein.\n\n    NCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of this security advisory. This includes damage resulting from the inaccuracy of incompleteness of the information contained in the advisory.\n    This security advisory is subject to Dutch law. All disputes related to or arising from the use of this advisory will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings."
      },
      {
        "category": "description",
        "text": "Microsoft heeft kwetsbaarheden verholpen in Exchange.",
        "title": "Feiten"
      },
      {
        "category": "description",
        "text": "Een kwaadwillende kan de kwetsbaarheden misbruiken om zich voor te doen als andere gebruiker, zich verhoogde rechten toe te kennen en willekeurige code uit te voeren met rechten van het proces.\n\nVan de kwetsbaarheid met kenmerk CVE-2026-96940 is eerder al een out-of-band update verschenen, maar is ook opgenomen in deze cumulatieve update.\n",
        "title": "Interpretaties"
      },
      {
        "category": "description",
        "text": "Microsoft heeft updates beschikbaar gesteld waarmee de beschreven kwetsbaarheden worden verholpen. We raden u aan om deze updates te installeren. Meer informatie over de kwetsbaarheden, de installatie van de updates en eventuele work-arounds vindt u op:\n\nhttps://portal.msrc.microsoft.com/en-us/security-guidance",
        "title": "Oplossingen"
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      },
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      {
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        "text": "Stack-based Buffer Overflow",
        "title": "CWE-121"
      },
      {
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        "text": "Improper Verification of Cryptographic Signature",
        "title": "CWE-347"
      },
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        "text": "Deserialization of Untrusted Data",
        "title": "CWE-502"
      },
      {
        "category": "general",
        "text": "Inclusion of Functionality from Untrusted Control Sphere",
        "title": "CWE-829"
      },
      {
        "category": "general",
        "text": "Incorrect Authorization",
        "title": "CWE-863"
      },
      {
        "category": "general",
        "text": "Weak Authentication",
        "title": "CWE-1390"
      }
    ],
    "publisher": {
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      "name": "Nationaal Cyber Security Centrum",
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    },
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}



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