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    "cveMetadata": {
        "cveId": "CVE-2026-56766",
        "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "state": "PUBLISHED",
        "assignerShortName": "VulnCheck",
        "dateReserved": "2026-06-22T21:55:17.942Z",
        "datePublished": "2026-06-25T18:01:07.362Z",
        "dateUpdated": "2026-07-14T21:34:18.775Z"
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                "dateUpdated": "2026-07-14T21:34:18.775Z"
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            "title": "Hydra - Stack Buffer Overflow in NTLM Authentication Handler",
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                {
                    "lang": "en",
                    "value": "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."
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            ],
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                "x_open-source"
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            "datePublic": "2026-05-19T00:00:00.000Z",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "cweId": "CWE-121",
                            "description": "Stack-based Buffer Overflow",
                            "type": "CWE"
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                    ]
                }
            ],
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                {
                    "vendor": "vanhauser-thc",
                    "product": "thc-hydra",
                    "defaultStatus": "unaffected",
                    "packageURL": "pkg:github/vanhauser-thc/thc-hydra",
                    "versions": [
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                            "version": "0",
                            "status": "affected",
                            "versionType": "custom",
                            "lessThanOrEqual": "9.7"
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                            "status": "unaffected",
                            "version": "9cc84c20e75f5fef6bb1790bb9ada2afad2204e2",
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                        "attackComplexity": "LOW",
                        "attackRequirements": "NONE",
                        "privilegesRequired": "NONE",
                        "userInteraction": "ACTIVE",
                        "vulnConfidentialityImpact": "HIGH",
                        "subConfidentialityImpact": "NONE",
                        "vulnIntegrityImpact": "HIGH",
                        "subIntegrityImpact": "NONE",
                        "vulnAvailabilityImpact": "HIGH",
                        "subAvailabilityImpact": "NONE",
                        "exploitMaturity": "NOT_DEFINED",
                        "Safety": "NOT_DEFINED",
                        "Automatable": "NOT_DEFINED",
                        "Recovery": "NOT_DEFINED",
                        "valueDensity": "NOT_DEFINED",
                        "vulnerabilityResponseEffort": "NOT_DEFINED",
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                        "baseScore": 8.6,
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                        "userInteraction": "REQUIRED",
                        "scope": "UNCHANGED",
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                    "url": "https://github.com/vanhauser-thc/thc-hydra/commit/9cc84c20e75f5fef6bb1790bb9ada2afad2204e2",
                    "name": "Patch Commit",
                    "tags": [
                        "patch"
                    ]
                },
                {
                    "url": "https://www.vulncheck.com/advisories/hydra-stack-buffer-overflow-in-ntlm-authentication-handler",
                    "tags": [
                        "third-party-advisory"
                    ]
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "Tristan Madani",
                    "type": "finder"
                }
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        "adp": [
            {
                "metrics": [
                    {
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                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-06-25T18:33:07.811052Z",
                                "id": "CVE-2026-56766",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
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                                        "Technical Impact": "total"
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                                "role": "CISA Coordinator",
                                "version": "2.0.3"
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                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
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                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-06-25T18:34:53.467Z"
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