Microsoft Windows Print Spooler: Local privilege escalation (use after free)
Summary
A use-after-free vulnerability in the Windows Print Spooler Components allows an authorized local attacker to elevate privileges. An attacker with a low-privilege account on an affected system can gain higher rights, potentially SYSTEM level. No user interaction is required, but local access and a valid account are needed. Exploitation has not been observed.
Affected
- Windows 10 Version 1607 and Windows Server 2016 (including Server Core): builds before 10.0.14393.9688
- Windows 10 Version 1809 and Windows Server 2019 (including Server Core): builds before 10.0.17763.9487
- Windows 10 Version 21H2: builds before 10.0.19044.7846
- Windows 10 Version 22H2: builds before 10.0.19045.7846
- Windows 11 Version 23H2: builds before 10.0.22631.7711
- Windows 11 Version 24H2: builds before 10.0.26100.9974
- Windows 11 Version 25H2 and 26H2: builds before 10.0.26200.9974 and 10.0.26300.9974
- Windows 11 Version 26H1: builds before 10.0.28000.3501
- Windows Server 2022: builds before 10.0.20348.5870
- Windows Server 2025: unknown, verify on the MSRC advisory
Fixed in
- Fixed by the November 2026 cumulative update for each affected build (Microsoft Patch Tuesday, 10 November 2026)
- Specific KB numbers: Unknown.
Workaround
- Unknown. No vendor workaround was identified in the sources reviewed.
Exploitation
- No exploitation in the wild is known.
- CISA SSVC: Exploitation none, Automatable no, Technical Impact total.
- Exploit code maturity is rated Unproven (E:U).
- No public proof of concept was found.
Our recommendation
- Install the November 2026 Windows updates on all affected systems, starting with workstations, terminal servers and print servers.
- Check the build numbers against the MSRC advisory before rollout.
- Where printing is not required, disable the Print Spooler service.
- Limit local logon to trusted users and monitor for unexpected privilege changes.
Information from Microsoft (Patch Tuesday November 2026)
- Severity (Microsoft)
- Important
- Impact
- Elevation of privilege – Windows Print Spooler Components
- Status on Patch Tuesday
- Neither exploited nor publicly disclosed
- Exploitability assessment
- Exploitation less likely
- Product family
- Windows, Windows ESU (Extended Security Updates)
- Updates (KB)
- KB5131291, KB5131085, KB5131096, KB5131090, KB5131087, KB5132061
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- CVE.org record CVE-2026-112978 www.cve.org
- Microsoft Security Response Center advisory CVE-2026-112978 msrc.microsoft.com
- Tenable: Microsoft November 2026 Patch Tuesday www.tenable.com
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 11 Nov 2026, 04:14.
Original description (NVD)
Use after free in Windows Print Spooler Components 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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