{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-87929",
        "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "state": "PUBLISHED",
        "assignerShortName": "VulnCheck",
        "dateReserved": "2026-09-09T16:12:31.422Z",
        "datePublished": "2026-09-09T16:45:00.096Z",
        "dateUpdated": "2026-09-24T14:21:31.142Z"
    },
    "containers": {
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                "dateUpdated": "2026-09-24T14:21:31.142Z"
            },
            "datePublic": "2026-09-09T00:00:00.000Z",
            "title": "MaxSite CMS through 109.6 Authentication Bypass via Hardcoded Encryption Key",
            "descriptions": [
                {
                    "lang": "en",
                    "value": "MaxSite CMS through 109.6 ships with a hardcoded session encryption key in application/config/config.php that is never changed during installation, allowing unauthenticated attackers to forge administrator session cookies. Attackers can mint a malicious ci_session cookie with administrator privileges by computing an HMAC-SHA1 using the publicly known encryption key, bypassing authentication checks in is_login() and mso_check_allow() functions."
                }
            ],
            "tags": [
                "x_open-source",
                "unsupported-when-assigned"
            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "cweId": "CWE-321",
                            "description": "Use of Hard-coded Cryptographic Key",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "defaultStatus": "unaffected",
                    "vendor": "MaxSite",
                    "product": "MaxSite CMS",
                    "packageURL": "pkg:github/maxsite/cms",
                    "repo": "https://github.com/maxsite/cms",
                    "versions": [
                        {
                            "version": "0.78",
                            "lessThanOrEqual": "109.6",
                            "status": "affected",
                            "versionType": "custom"
                        }
                    ]
                }
            ],
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                                    "versionStartIncluding": "0.78",
                                    "versionEndIncluding": "109.6"
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            ],
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                {
                    "cvssV4_0": {
                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "attackRequirements": "NONE",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "vulnConfidentialityImpact": "HIGH",
                        "subConfidentialityImpact": "NONE",
                        "vulnIntegrityImpact": "HIGH",
                        "subIntegrityImpact": "NONE",
                        "vulnAvailabilityImpact": "HIGH",
                        "subAvailabilityImpact": "NONE",
                        "version": "4.0",
                        "baseSeverity": "CRITICAL",
                        "baseScore": 9.3,
                        "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
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                        "scope": "UNCHANGED",
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                        "integrityImpact": "HIGH",
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                        "baseScore": 9.8,
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
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            ],
            "references": [
                {
                    "url": "https://github.com/maxsite/cms",
                    "tags": [
                        "product"
                    ]
                },
                {
                    "url": "https://github.com/EviL0rd/maxsite-cve4/blob/main/2026.09.08-maxsite-cms-hardcoded-session-key-auth-bypass.md",
                    "tags": [
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                    "tags": [
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                },
                {
                    "name": "VulnCheck Advisory: MaxSite CMS through 109.6 Authentication Bypass via Hardcoded Encryption Key",
                    "tags": [
                        "third-party-advisory"
                    ],
                    "url": "https://www.vulncheck.com/advisories/maxsite-cms-through-109.6-authentication-bypass-via-hardcoded-encryption-key"
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "EVIL0RD",
                    "type": "finder"
                }
            ],
            "source": {
                "discovery": "EXTERNAL"
            },
            "x_generator": {
                "engine": "vulncheck-endgame"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-09-14T13:40:16.278801Z",
                                "id": "CVE-2026-87929",
                                "options": [
                                    {
                                        "Exploitation": "poc"
                                    },
                                    {
                                        "Automatable": "yes"
                                    },
                                    {
                                        "Technical Impact": "total"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
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                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
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                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-09-14T13:40:25.541Z"
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}