Windows Deployment Services: Information disclosure via path traversal
Summary
Windows Deployment Services on Windows Server 2016, 2019, 2022 and 2025 contains a relative path traversal vulnerability (CWE-23). An unauthorized attacker with network access can read information from the server, but cannot change data or disrupt the service. Exploitation requires high attack complexity, and no public exploit or active exploitation is known.
Affected
- Windows Server 2016 and Server Core installation: builds before 10.0.14393.9688
- Windows Server 2019 and Server Core installation: builds before 10.0.17763.9487
- Windows Server 2022: builds before 10.0.20348.5870
- Windows Server 2025 and Server Core installation: builds before 10.0.26100.33822
Fixed in
- Install the Microsoft security update from November 2026 that brings the builds to the listed fixed versions or later.
- Cumulative update KB numbers reported by third parties (KB5131080, KB5131085) are unverified.
Workaround
Unknown.
Exploitation
- Microsoft SSVC assessment: no exploitation, not automatable
- Rapid7: exploitation less likely, not publicly disclosed
- No public proof of concept or Metasploit module found at the time of research
Our recommendation
- Apply the November 2026 cumulative update to all affected Windows Server hosts, prioritising WDS servers reachable from guest, branch or VPN networks.
- Verify the installed build and the update on MSRC or the Microsoft Update Catalog before rollout.
- Check whether WDS is reachable beyond the internal deployment network.
- Until patched, limit WDS to the deployment VLAN and block its ports from untrusted networks.
- Check older hosts outside the listed builds, including Windows Server 2012/R2, whose status is not confirmed.
Information from Microsoft (Patch Tuesday November 2026)
- Severity (Microsoft)
- Important
- Impact
- Information disclosure – Windows Deployment Services
- 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, KB5131090, KB5131080, KB5131077
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Update Guide: CVE-2026-118213 msrc.microsoft.com
- CVE Record CVE-2026-118213 www.cve.org
- Rapid7: Patch Tuesday November 2026 www.rapid7.com
- Senserva: KB5131080 senserva.com
- Senserva: KB5131085 senserva.com
- Strix: CVE-2026-118213 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 11 Nov 2026, 15:17.
Original description (NVD)
Relative path traversal in Windows Deployment Services allows an unauthorized attacker to disclose information over a network.
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.
We check whether your systems are affected, install updates and close the gap – continuously with the System Health Checker if you wish.