Microsoft Windows: Use-after-free in Broadcast DVR User Service
Summary
A use-after-free flaw (CWE-416) in the Windows Broadcast DVR User Service allows a local user with an existing low-privileged account to elevate privileges. Successful exploitation can give an attacker SYSTEM rights, for example after a phishing or account compromise. The NVD record rates it 7.0 (High) with local attack vector and high attack complexity, but the vector string in one mirror conflicts with the text, so NVD should be checked.
Affected
- Windows 10 Version 1809 (builds below 10.0.17763.9376)
- Windows 10 Version 21H2 (builds below 10.0.19044.7807)
- Windows 10 Version 22H2 (builds below 10.0.19045.7807)
- Windows 11 Version 23H2 (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 2019, including Server Core installation (builds below 10.0.17763.9376)
Fixed in
October 13, 2026 cumulative updates, as listed by a secondary source (verify KB numbers on MSRC):
- KB5126651: Windows 10 1809 and Server 2019 (build 17763.9376)
- KB5126657: Windows 10 21H2 and 22H2 (builds 19044.7807 and 19045.7807)
- KB5126653: Windows 11 23H2 (build 22631.7652)
- KB5127648: Windows 11 24H2, 25H2 and 26H2 (builds 26100, 26200 and 26300 with .9711)
- KB5127646: Windows 11 26H1 (build 28000.3231)
Workaround
Unknown. No workaround was found in the sources reviewed; patching is the remedy listed.
Exploitation
- No evidence found of exploitation in the wild and no public proof of concept found in the sources reviewed.
- CISA SSVC assessment: exploitation none, not automatable, total technical impact.
- EPSS about 0.25% according to one aggregator.
- The CISA KEV catalog and the MSRC exploitation flag were not checked.
Our recommendation
- Install the October 2026 cumulative update for each affected Windows version (see Fixed).
- Prioritise servers, RDS/terminal servers and shared PCs.
- Check whether any Windows 10 1809 systems are still in use; these are out of support for most editions.
- Restrict local logon rights and review local accounts.
- Recheck CISA KEV and the MSRC advisory before relying on the exploitation status.
Information from Microsoft (Patch Tuesday October 2026)
- Severity (Microsoft)
- Important
- Impact
- Elevation of privilege – Windows Broadcast DVR User Service
- Status on Patch Tuesday
- Neither exploited nor publicly disclosed
- Exploitability assessment
- Exploitation less likely
- Product family
- Windows, Windows ESU (Extended Security Updates)
- Updates (KB)
- KB5126651, KB5126657, KB5126653, KB5127648, KB5127646
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Update Guide: CVE-2026-105722 msrc.microsoft.com
- CNA data mirror (vulners.com) vulners.com
- NVD record mirror (vulners.com) vulners.com
- PT-2026-111996 cumulative update listing vulners.com
- Qualys October 2026 Patch Tuesday review blog.qualys.com
- Rapid7 advisory mirror (vulners.com) vulners.com
- Strix.ai CVE-2026-105722 www.strix.ai
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 4 Nov 2026, 09:46.
Original description (NVD)
Use after free in Windows Broadcast DVR User Service 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.
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