Windows Telephony Service
CVE-2026-20931 — Windows Telephony Service Elevation of Privilege Vulnerability
Executive Summary
External control of file name or path in Windows Telephony Service allows an authorized attacker to elevate privileges over an adjacent network.
Overview
8
CVSS HIGH
Important
MS Severity
Not Exploited
MS Exploit Status
Exploitation Unlikely
MS Exploit Likelihood
CVSS Vector
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
ATTACK VECTOR
Adjacent_network
ATTACK COMPLEXITY
Low
PRIVILEGES REQUIRED
Low
USER INTERACTION
None
SCOPE
Unchanged
CONFIDENTIALITY
High
INTEGRITY
High
AVAILABILITY
High
EXPLOIT CODE MATURITY
Unproven
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 7.0
EPSS Score
0.0075
probability of exploitation in the next 30 days
0.50073 percentile - updated 2026-06-21
View on FIRST.org
Affected Products
29 affected products
| Product | KB Article | Severity | Impact | Restart Required |
|---|---|---|---|---|
| Windows 10 Version 1607 for 32-bit Systems | 5073722 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows 10 Version 1607 for x64-based Systems | 5073722 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows 10 Version 1809 for 32-bit Systems | 5073723 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows 10 Version 1809 for x64-based Systems | 5073723 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows 10 Version 21H2 for 32-bit Systems | 5073724 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows 10 Version 21H2 for ARM64-based Systems | 5073724 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows 10 Version 21H2 for x64-based Systems | 5073724 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows 10 Version 22H2 for 32-bit Systems | 5073724 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows 10 Version 22H2 for ARM64-based Systems | 5073724 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows 10 Version 22H2 for x64-based Systems | 5073724 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows 11 Version 23H2 for ARM64-based Systems | 5073455 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows 11 Version 23H2 for x64-based Systems | 5073455 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows 11 Version 24H2 for ARM64-based Systems | 5074109 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows 11 Version 24H2 for x64-based Systems | 5074109 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows 11 Version 25H2 for ARM64-based Systems | 5074109 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows 11 Version 25H2 for x64-based Systems | 5074109 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows Server 2008 for 32-bit Systems Service Pack 2 5073697 (Monthly Rollup) 5073700 (Security Only) Important Elevation of Privilege 5071504 Base: 8.0 Temporal: 7.0 Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C 6.0.6003.23717 Yes None Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation) 5073697 (Monthly Rollup) 5073700 (Security Only) Important Elevation of Privilege 5071504 Base: 8.0 Temporal: 7.0 Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C 6.0.6003.23717 Yes None Windows Server 2008 for x64-based Systems Service Pack 2 5073697 (Monthly Rollup) 5073700 (Security Only) Important Elevation of Privilege 5071504 Base: 8.0 Temporal: 7.0 Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C 6.0.6003.23717 Yes None Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation) 5073697 (Monthly Rollup) 5073700 (Security Only) Important Elevation of Privilege 5071504 Base: 8.0 Temporal: 7.0 Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C 6.0.6003.23717 Yes None Windows Server 2008 R2 for x64-based Systems Service Pack 1 5073695 (Monthly Rollup) 5073699 (Security Only) Important Elevation of Privilege 5071501 Base: 8.0 Temporal: 7.0 Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C 6.1.7601.28117 Yes None Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) 5073695 (Monthly Rollup) 5073699 (Security Only) Important Elevation of Privilege 5071501 Base: 8.0 Temporal: 7.0 Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C 6.1.7601.28117 Yes None Windows Server 2012 | 5073698 (Monthly Rollup) |
Important | Elevation of Privilege | Yes |
| Windows Server 2012 (Server Core installation) | 5073698 (Monthly Rollup) |
Important | Elevation of Privilege | Yes |
| Windows Server 2012 R2 | 5073696 (Monthly Rollup) |
Important | Elevation of Privilege | Yes |
| Windows Server 2012 R2 (Server Core installation) | 5073696 (Monthly Rollup) |
Important | Elevation of Privilege | Yes |
| Windows Server 2016 | 5073722 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows Server 2016 (Server Core installation) | 5073722 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows Server 2019 | 5073723 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows Server 2019 (Server Core installation) | 5073723 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows Server 2022 | 5073457 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows Server 2022 (Server Core installation) | 5073457 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows Server 2022, 23H2 Edition (Server Core installation) | 5073450 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows Server 2025 | 5073379 (Security Update) |
Important | Elevation of Privilege | Yes |
| Windows Server 2025 (Server Core installation) | 5073379 (Security Update) |
Important | Elevation of Privilege | Yes |
Patches
10 patches
| Article | Type | Restart |
|---|---|---|
5073722 |
Security Update | Yes |
5073723 |
Security Update | Yes |
5073724 |
Security Update | Yes |
5073455 |
Security Update | Yes |
5074109 |
Security Update | Yes |
5073698 |
Monthly Rollup | Yes |
5073696 |
Monthly Rollup | Yes |
5073457 |
Security Update | Yes |
5073450 |
Security Update | Yes |
5073379 |
Security Update | Yes |
Known Exploits
No known exploits have been linked for this CVE yet. When available, exploit references will be sourced from public repositories and may be unverified, incomplete, or non-functional. Always review code carefully before use in any environment.
Acknowledgments
Sergey Bliznyuk with Positive Technologies
References
On This Page