CVE-2026-83580: Windows Client-Side Caching (CSC) Service Elevation of Privilege Vulnerability
Heap-based buffer overflow in Windows Client-Side Caching (CSC) Service allows an authorized attacker to elevate privileges locally.
Other sources
Windows Client-Side Caching (CSC) Service Elevation of Privilege Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
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Fixed in 6.3.9600.23470Patch KB5126836 - Upgrade
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Fixed in 10.0.14393.9612Patch KB5126868 - Upgrade
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Fixed in 10.0.22631.7652Patch KB5126653 - Upgrade
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Fixed in 10.0.26100.9711Patch KB5127648 - Upgrade
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Fixed in 6.2.9200.26434Patch KB5126835 - Upgrade
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Fixed in 10.0.26100.33650Patch KB5126646 - Upgrade
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Fixed in 10.0.28000.3231Patch KB5127646 - Upgrade
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Fixed in 10.0.26200.9711Patch KB5127648 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.17763.9376Patch KB5126651 - Upgrade
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Fixed in 10.0.19044.7807Patch KB5126657 - Upgrade
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Fixed in 10.0.20348.5761Patch KB5126655 - Upgrade
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Fixed in 10.0.26300.9711Patch KB5127648
Event History
Frequently Asked Questions
What level of access does an attacker need to exploit this issue?
The attacker must already be authorized on the affected system and able to execute an attack locally. The available information does not indicate that remote exploitation or user interaction is required.
What is the likely impact if exploitation succeeds?
Successful exploitation allows local elevation of privilege. The supplied severity vector indicates high potential impact to confidentiality, integrity, and availability.
Which systems should be included in triage?
Triage Microsoft Windows 10 and Windows 11, plus Windows Server 2012, 2012 R2, 2016, 2019, 2022, and 2025 systems. The data does not identify specific affected builds, editions, or update levels.