Microsoft Windows Error Reporting: Elevation of privilege via untrusted pointer dereference
Summary
Windows Error Reporting, the built-in Windows crash-reporting component, contains an untrusted pointer dereference that allows a local attacker to elevate privileges. The attacker needs a valid logon with low privileges on the affected system and must run code locally. A successful attack could grant higher privileges, which is especially relevant on shared or multi-user systems such as terminal servers.
Affected
- Windows 11 version 23H2 (x64 and ARM64): builds below 10.0.22631.7652
- Windows 11 version 24H2: builds below 10.0.26100.9711
- Windows 11 version 25H2: builds below 10.0.26200.9711
- Windows 11 version 26H1: builds below 10.0.28000.3231
- Windows 11 version 26H2: builds below 10.0.26300.9711
- Windows Server 2025 (including Server Core): builds below 10.0.26100.33650
Fixed in
- Windows 11 version 23H2: 10.0.22631.7652 or later
- Windows 11 version 24H2: 10.0.26100.9711 or later
- Windows 11 version 25H2: 10.0.26200.9711 or later
- Windows 11 version 26H1: 10.0.28000.3231 or later
- Windows 11 version 26H2: 10.0.26300.9711 or later
- Windows Server 2025: 10.0.26100.33650 or later
- Confirm the KB number on the MSRC update guide page, as third-party sources list different KB numbers.
Workaround
Unknown. No workaround is documented; applying the security update is the only confirmed fix.
Exploitation
- CISA SSVC: exploitation none, automatable no, technical impact total.
- No public proof of concept or reports of in-the-wild exploitation were found.
- Not listed in the CISA KEV catalog at the time of research.
- EPSS was about 0.0035 at the last NVD mirror update.
Our recommendation
- Install the October 2026 cumulative update on affected Windows 11 and Server 2025 systems, prioritising shared, terminal and multi-user systems.
- Verify the installed build is at or above the fixed version listed above.
- Limit local logons on shared systems to users who need them.
- Re-check the CVE in KEV and exploit sources in the coming weeks.
Information from Microsoft (Patch Tuesday October 2026)
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- MSRC Security Update Guide: CVE-2026-83826 msrc.microsoft.com
- VulDB: CVE-2026-83826 vuldb.com
- NVD mirror (Vulners): CVE-2026-83826 vulners.com
- OpenCVE: CVE-2026-83826 app.opencve.io
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 2 Nov 2026, 02:55.
Original description (NVD)
Untrusted pointer dereference in Windows Error Reporting allows an authorized attacker to elevate privileges locally.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
Affected? We can help.
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