CVE-2026-77894
Analyzed
Analyzed - Analysis Complete
Windows Installer Race Condition Privilege Escalation
Vulnerability report for CVE-2026-77894, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-09-08
Last updated on: 2026-09-24
Assigner: Microsoft Corporation
Description
Description
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Installer allows an authorized attacker to elevate privileges locally.
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| microsoft | windows_installer | * |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-362 | The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently. |
| CWE-416 | The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer. |
