CVE-2026-22561

Uncontrolled search path elements in Anthropic Claude for Windows installer (Claude Setup.exe) versions prior to 1.1.3363 allow local privilege escalation via DLL search-order hijacking. The installer loads DLLs (e.g., profapi.dll) from its own directory after UAC elevation, enabling arbitrary code execution if a malicious DLL is planted alongside the installer.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://trust.anthropic.com/resources?s=1cvig6ldp3zvuj1yffzr11&name=cve-2026-22561-dll-search-order-hijacking-in-claude-for-windows-installer	Vendor Advisory

Configurations

Configuration 1 (hide)

AND

cpe:2.3:a:anthropic:claude:*:*:*:*:*:*:*:*

cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*

History

06 Apr 2026, 16:58

Type	Values Removed	Values Added
CPE		cpe:2.3:o:microsoft:windows:-:::::::* cpe:2.3:a:anthropic:claude::::::::
CWE		CWE-427
References	~~() https://trust.anthropic.com/resources?s=1cvig6ldp3zvuj1yffzr11&name=cve-2026-22561-dll-search-order-hijacking-in-claude-for-windows-installer -~~	() https://trust.anthropic.com/resources?s=1cvig6ldp3zvuj1yffzr11&name=cve-2026-22561-dll-search-order-hijacking-in-claude-for-windows-installer - Vendor Advisory
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.8
First Time		Anthropic Anthropic claude Microsoft Microsoft windows

31 Mar 2026, 16:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-31 16:16

Updated : 2026-04-06 16:58

NVD link : CVE-2026-22561

Mitre link : CVE-2026-22561

CVE.ORG link : CVE-2026-22561

JSON object : View

Products Affected

anthropic

claude

microsoft

windows

CWE

CWE-427

Uncontrolled Search Path Element

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