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    1 vulnerability by vanhauser-thc

    CVE-2026-56766 (GCVE-0-2026-56766)

    Vulnerability from cvelistv5 – Published: 2026-06-25 18:01 – Updated: 2026-06-25 18:34 X_Open Source
    VLAI
    Title
    Hydra - Stack Buffer Overflow in NTLM Authentication Handler
    Summary
    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.
    Severity
    8.6 (High)
    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
    8.8 (High)
    CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
    SSVC
    Exploitation: none Automatable: no Technical Impact: total
    CISA Coordinator (v2.0.3)
    CWE
    • CWE-121 - Stack-based Buffer Overflow
    Assigner
    References
    Impacted products
    Vendor Product Version
    vanhauser-thc thc-hydra Affected: 0 , ≤ 9.7 (custom)
    Unaffected: 9cc84c20e75f5fef6bb1790bb9ada2afad2204e2 (git)
    		Create a notification for this product.
    Date Public
    2026-05-19 00:00
    Credits
    Tristan Madani
    Show details on NVD website
    To clipboard 

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