Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-56766— Hydra - Stack Buffer Overflow in NTLM Authentication Handler

Quick assessment

Affected
vanhauser-thc thc-hydra
Exploitation
Public or AI PoC available; prioritize validation
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

vanhauser-thc thc-hydra是vanhauser-thc个人开发者开源的一款网络认证破解工具。 vanhauser-thc thc-hydra 9.7及之前版本存在缓冲区错误漏洞，该漏洞源于处理恶意NTLM Type-2挑战时SMTP、POP3、IMAP、NNTP、HTTP、HTTP-Proxy和HTTP-Proxy-Urlenum模块中的NTLM身份验证存在栈缓冲区溢出，恶意服务器可通过发送包含超长域字符串的特制NTLM Type-2挑战，使base64编码响应数据溢出500字节的栈缓

CVSS 8.8 · High EPSS 2.44% · P84

Public Exploits 1

ExploitDB · 1 EDB-52622 [remote]

Possible ATT&CK Techniques 1 AI

T1190 · Exploit Public-Facing Application

Affected Version Matrix 2

VendorProduct Version RangeStatus
vanhauser-thc thc-hydra ≤ 9.7 affected
9cc84c20e75f5fef6bb1790bb9ada2afad2204e2 unaffected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-56766

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Hydra - Stack Buffer Overflow in NTLM Authentication Handler
Source: CVE Program / CVE List V5
Vulnerability Description
Hydra through 9.7, fixed in commit 9cc84c2, contains a stack buffer overflow in NTLM authentication across SMTP, POP3, IMAP, NNTP, HTTP, HTTP-Proxy, and HTTP-Proxy-Urlenum modules when processing malicious NTLM Type-2 challenges. A malicious server can send a crafted NTLM Type-2 challenge with an excessively long domain string, causing base64-encoded response data to overflow a 500-byte stack buffer by 18 to 330 bytes, enabling remote code execution on systems without stack protection.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
栈缓冲区溢出
Source: CVE Program / CVE List V5
Vulnerability Title
vanhauser-thc thc-hydra 缓冲区错误漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
vanhauser-thc thc-hydra是vanhauser-thc个人开发者开源的一款网络认证破解工具。 vanhauser-thc thc-hydra 9.7及之前版本存在缓冲区错误漏洞，该漏洞源于处理恶意NTLM Type-2挑战时SMTP、POP3、IMAP、NNTP、HTTP、HTTP-Proxy和HTTP-Proxy-Urlenum模块中的NTLM身份验证存在栈缓冲区溢出，恶意服务器可通过发送包含超长域字符串的特制NTLM Type-2挑战，使base64编码响应数据溢出500字节的栈缓
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
vanhauser-thc thc-hydra 0 ~ 9.7 -

II. Public POCs for CVE-2026-56766

# POC Description Source Link Shenlong Link
AI-Generated POC Premium
Qwen3.6-35B-A3B · 10863 chars
Pro+ exclusive includes:
Vulnerability reproduction recording (real sandbox build + trigger, exclusive)
In-depth vulnerability mechanism
Trigger conditions & impact
Full executable POC code
Exploit chain & mitigation
POC zip download
100+ AI POC generations per month

III. Intelligence Information for CVE-2026-56766

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-56766 (1)

Vendor Advisories for CVE-2026-56766 (1)

IV. Related Vulnerabilities

Same weakness: CWE-121

V. Comments for CVE-2026-56766

No comments yet

Leave a comment