Skip to main content

WPDBusEnum Service CVE-2026-88133

| EUVDEUVD-2026-100098 HIGH
Improper Link Resolution Before File Access (CWE-59)
2026-10-13 secure@microsoft.com GHSA-xrx8-44m8-rqrq
7.8
CVSS 3.1 · Vendor: microsoft
View

Attack ChainAIDerived

Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain

  1. Access
    Obtain local low-privileged access
  2. Delivery
    Plant malicious symlink/junction for service
  3. Exploit
    Trigger Portable Device Enumerator operation
  4. Execution
    Redirect privileged write via CWE-59
  5. Impact
    Execute code as SYSTEM

Vulnerability Assessment

Weakness
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V5 - File Handling Symlink resolution safety
Exploitation Conditions

Requires the attacker to already possess authenticated local access as a low-privileged user on an affected Windows system; this is not remotely exploitable (AV:L). Exploitation targets the Windows Portable Device Enumerator Service and, per CWE-59, depends on manipulating file-system links (symlinks/junctions) to redirect a privileged operation, which typically requires winning a race condition - consistent with CISA's Automatable: no. No special non-default configuration is called out in the advisory; the limiting factors are the local-access prerequisite, the existing low-privilege authentication requirement, and the link-following race, all of which reduce realistic risk below the raw 7.8 score.

Impact

This is a credible but second-tier priority. The CVSS 3.1 vector (AV:L/AC:L/PR:L/UI:N/S:U, C:H/I:H/A:H) describes a local elevation-of-privilege flaw requiring an attacker to already have authenticated low-privilege access to the host, yielding total compromise (SYSTEM) on success - consistent with the CISA SSVC rating of Technical Impact: total. However, multiple signals argue against emergency patching: SSVC lists Exploitation: none and Automatable: no, there is no CISA KEV listing, and no public exploit code is identified. No EPSS score was supplied in the input, so widespread-exploitation probability cannot be quantified here. The signals are mutually consistent rather than conflicting: high technical impact but local-only reach, authentication required, and no evidence of real-world use. The CWE-59 (link following) root cause means exploitation typically hinges on winning a file-operation race or abusing a symlink against the service, which supports the Automatable: no judgment. Net: a real local-EoP issue worth routine patching in the normal Patch Tuesday cycle, not a drop-everything emergency, absent new exploitation evidence.

Exploit ScenarioDerived

An attacker who already has a low-privileged foothold on a Windows host (e.g., via phishing, a compromised standard user account, or chained from a separate RCE) abuses improper authorization and link-following (CWE-59) in the Portable Device Enumerator Service to redirect a privileged file operation to an attacker-controlled target. This elevates them to SYSTEM, giving full control of the machine. No public proof-of-concept is identified at time of analysis.

This Week Schedule remediation this week. Why: HIGH severity (CVSS 7.0-8.9).
Patch available 0.4% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAIv1 – Oct 13, 2026

Local privilege escalation in the Windows Portable Device Enumerator Service (WPDBusEnum) allows an authenticated, low-privileged user on an affected Windows host to redirect a privileged file-system operation and elevate to a higher-integrity context, with high confidentiality, integrity and availability impact (CVSS 7.8, CWE-59 link following). Exploitation is strictly local (AV:L, PR:L, UI:N) and hinges on planting a symbolic link or junction so that a privileged file operation follows it - typically requiring a race to be won, which is why CISA's SSVC rates the issue non-automatable with exploitation observed as none. Microsoft has published a remediating update, and no public exploit identified at time of analysis; no confirmed actively exploited (CISA KEV) status is associated with this issue.

RemediationAI

Patch available per vendor advisory: apply the current Microsoft cumulative security update for each affected build so that it reaches or exceeds the fixed build thresholds published by EUVD - 10.0.14393.9612 (Win10 1607/Server 2016), 10.0.17763.9376 (Win10 1809/Server 2019), 10.0.19044.7807 (Win10 21H2/22H2), 10.0.22631.7652 (Win11 23H2), 10.0.26100.9711 and 10.0.26100.33650 (Win11 24H2 / Server 2025), 10.0.26200.9711 (Win11 25H2), 10.0.28000.3231 (Win11 26H1), 10.0.26300.9711 (Win11 26H2), 6.2.9200.26434 (Server 2012), 6.3.9600.23470 (Server 2012 R2) and 10.0.20348.5761 (Server 2022); details are in https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88133. Because the attack is local and requires an already-authenticated low-privileged account, the most effective compensating controls are to reduce and audit the population holding local interactive logon or local service-account rights on the affected hosts, and to enable file-system auditing/monitoring for symbolic-link, junction and mount-point creation in directories writable by unprivileged users (trade-off: audit volume and storage overhead, and it is detective rather than preventive). Hardening that removes the need for portable-device handling entirely - for example disabling the Portable Device Enumerator Service on servers and locked-down images that never attach WPD/MTP hardware - will cut the attack surface but breaks portable device and media transfer functionality and is not a vendor-recommended substitute for patching (trade-off: functional regression plus potential management-tool side effects). No special configuration is required for exposure, so configuration review alone does not mitigate the issue; the update is the primary fix.

Affected VersionsENISA

Windows Server 2012 6.2.9200.0 <6.2.9200.26434
Windows Server 2012 (Server Core installation) 6.2.9200.0 <6.2.9200.26434
Windows 11 Version 23H2 10.0.22631.0 <10.0.22631.7652
Windows 10 Version 1607 10.0.14393.0 <10.0.14393.9612
Windows Server 2022 10.0.20348.0 <10.0.20348.5761
Windows Server 2012 R2 6.3.9600.0 <6.3.9600.23470
Windows 11 Version 24H2 10.0.26100.0 <10.0.26100.9711
Windows 11 version 26H1 10.0.28000.0 <10.0.28000.3231
Windows 10 Version 22H2 10.0.19045.0 <10.0.19044.7807
Windows Server 2012 R2 (Server Core installation) 6.3.9600.0 <6.3.9600.23470
Windows 11 Version 26H2 10.0.26300.0 <10.0.26300.9711
Windows Server 2019 10.0.17763.0 <10.0.17763.9376
Windows Server 2025 (Server Core installation) 10.0.26100.0 <10.0.26100.33650
Windows Server 2019 (Server Core installation) 10.0.17763.0 <10.0.17763.9376
Windows 10 Version 1809 10.0.17763.0 <10.0.17763.9376
Windows Server 2016 10.0.14393.0 <10.0.14393.9612
Windows 10 Version 21H2 10.0.19044.0 <10.0.19044.7807
Windows 11 Version 25H2 10.0.26200.0 <10.0.26200.9711
Windows Server 2025 10.0.26100.0 <10.0.26100.33650
Windows Server 2016 (Server Core installation) 10.0.14393.0 <10.0.14393.9612

Affected Packages

euvd windows_10_version_1607 fix: 10.0.14393.9612
euvd windows_10_version_1809 fix: 10.0.17763.9376
euvd windows_10_version_21h2 fix: 10.0.19044.7807
euvd windows_10_version_22h2 fix: 10.0.19044.7807
euvd windows_11_version_23h2 fix: 10.0.22631.7652
euvd windows_11_version_24h2 fix: 10.0.26100.9711
euvd windows_11_version_25h2 fix: 10.0.26200.9711
euvd windows_11_version_26h1 fix: 10.0.28000.3231
euvd windows_11_version_26h2 fix: 10.0.26300.9711
euvd windows_server_2012 fix: 6.2.9200.26434
euvd windows_server_2012_r2 fix: 6.3.9600.23470
euvd windows_server_2012_r2_server_core_installation fix: 6.3.9600.23470
euvd windows_server_2012_server_core_installation fix: 6.2.9200.26434
euvd windows_server_2016 fix: 10.0.14393.9612
euvd windows_server_2016_server_core_installation fix: 10.0.14393.9612
euvd windows_server_2019 fix: 10.0.17763.9376
euvd windows_server_2019_server_core_installation fix: 10.0.17763.9376
euvd windows_server_2022 fix: 10.0.20348.5761
euvd windows_server_2025 fix: 10.0.26100.33650
euvd windows_server_2025_server_core_installation fix: 10.0.26100.33650

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 20 packages in euvd

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

The root cause class is CWE-59, Improper Link Resolution Before File Access ('link following'), applied to the Windows Portable Device Enumerator Service - the component that enumerates and brokers access to portable devices (WPD/MTP-class hardware) on behalf of the operating system. Because that service performs file-system operations in a more privileged security context than the invoking user, a low-privileged local attacker who can create a symbolic link, junction, or mount point in a location the service later touches can cause the privileged write or read to follow the planted link and be redirected to an attacker-chosen target, yielding privilege elevation. The published CVSS:3.1 vector (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) confirms the prerequisite is existing low-privileged local authentication, that no user interaction is needed beyond the attacker's own actions, and that the scope of the resulting compromise is confined to the same security authority but with total technical impact once achieved. The race/link-following nature of the primitive is consistent with CISA SSVC recording Automatable: no, and the advisory does not describe any non-default configuration that must be present for exposure.

Know when the next one hits your stack

  • Watch products and get an email when something new is published
  • Check this CVE against your own stack and servers
  • Exploit and PoC references, threat intelligence from 22 sources

No credit card · 7-day full trial

Severity by source

Vendor (microsoft) PRIMARY 7.8 HIGH
AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
vuln.today AI 7.8 HIGH

Local authenticated low-priv user (AV:L/PR:L) abusing a service link-following flaw to reach SYSTEM yields total C/I/A impact with no scope change; AC:L retained per vendor despite the typical race.

3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
4.0 AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Primary rating from Vendor (microsoft).

CVSS VectorVendor: microsoft

Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Lifecycle Timeline

2
Patch available
Oct 13, 2026 - 20:20 EUVD
CVE Published
Oct 13, 2026 - 19:21 cve.org
HIGH 7.8

DescriptionCVE.org

Improper authorization in Windows Portable Device Enumerator Service allows an authorized attacker to elevate privileges locally.

Executive ViewAI

Why It Matters

A high-severity local privilege escalation in Microsoft Windows' Portable Device Enumerator Service (WPDBusEnum) could allow an authenticated low-privileged user on an affected endpoint to gain higher-integrity access, with potential impact to confidentiality, integrity, and availability on that host. Because exploitation is local and no public exploit identified at time of analysis, the immediate enterprise risk is concentrated in environments where standard users have endpoint access or where an attacker already holds a foothold; leadership should prioritize patching to prevent elevation from enabling broader compromise.

Business Impact: High
Compensating Controls

Apply vendor patch.

Threat Intelligence Overview

EPSS Score
0.4%
Top 66% exploitable
Prevalence
Ubiquitous
Core Microsoft Windows component across client and server editions
Vendor Status
Publicly Disclosed:No
Exploited:No
Latest Software Release:Exploitation More Likely
Data Quality
5 sources
Confidence: Medium

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity HIGH
CISA KEV No
Public POC No
EPSS 0.4%
Patch available Yes
Active threat No
Deciding rule
HIGH severity (CVSS 7.0-8.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision
Defer
Exploitation
None
System Exposure· derived
Small
Automatable
No
Human Impact
High
Technical Impact
Total

Priority Score

39
Low Medium High Critical
KEV: 0
EPSS: 0
CVSS: +39
PoC: 0
Weaponized: 0
Threat intel: 0
Gov advisory: 0

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy