CVE-2026-62729: Windows Telephony Service Elevation of Privilege Vulnerability

highCVSS 7CVE-2026-62729

Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Telephony Service allows an authorized attacker to elevate privileges locally.

CSIRTS triage

vendor: Microsoft product: Windows Telephony Service Privilege escalation

What: Race condition in Windows Telephony Service allows privilege elevation locally.
Who is affected: Authorized local users on systems running Windows Telephony Service.
Urgency: High priority; CVSS 7.0 for local privilege escalation by authorized users.
Action: Apply Microsoft security updates immediately for Windows Telephony Service.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 7
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-62729

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-627290.19% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 9% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-62729	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

critical[NEW] [critical] Microsoft Windows Products: Multiple vulnerabilitiescert-bund
unknownexploitedNCSC-2026-0284 [1.00] [M/H] Vulnerabilities patched in Microsoft Windowsncsc-nl
highCVE-2026-62729: Concurrent execution using shared resource with improper synchronization ('race condition') in…nvd

Recent advisories for Windows Telephony Service

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

highCVE-2026-62748: Concurrent execution using shared resource with improper synchronization ('race condition') in…nvd · 2026-08-11
highCVE-2026-62734: Concurrent execution using shared resource with improper synchronization ('race condition') in…nvd · 2026-08-11
highCVE-2026-62732: Heap-based buffer overflow in Windows Telephony Service allows an authorized attacker to eleva…nvd · 2026-08-11
highCVE-2026-62729: Concurrent execution using shared resource with improper synchronization ('race condition') in…nvd · 2026-08-11
highCVE-2026-62726: Use after free in Windows Telephony Service allows an authorized attacker to elevate privilege…nvd · 2026-08-11
highCVE-2026-62725: Use after free in Windows Telephony Service allows an authorized attacker to elevate privilege…nvd · 2026-08-11