{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-91939",
        "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "state": "PUBLISHED",
        "assignerShortName": "VulnCheck",
        "dateReserved": "2026-09-15T11:07:01.912Z",
        "datePublished": "2026-09-15T20:56:45.058Z",
        "dateUpdated": "2026-09-24T14:22:31.728Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
                "shortName": "VulnCheck",
                "dateUpdated": "2026-09-24T14:22:31.728Z"
            },
            "datePublic": "2026-09-13T00:00:00.000Z",
            "title": "Cotonti 1.0.0 Comments Plugin PHP Object Injection via ci Parameter",
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Cotonti 1.0.0 Comments plugin passes the ci GET parameter to unserialize() without allowed_classes restriction, allowing unauthenticated attackers to instantiate arbitrary PHP classes with attacker-controlled properties. Attackers can exploit PHP object injection through crafted serialized payloads to trigger gadget chains and achieve database manipulation or code execution."
                }
            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "description": "Deserialization of Untrusted Data",
                            "cweId": "CWE-502",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "vendor": "Cotonti",
                    "product": "Cotonti",
                    "defaultStatus": "unaffected",
                    "packageURL": "pkg:composer/cotonti/cotonti",
                    "repo": "https://github.com/Cotonti/Cotonti",
                    "programFiles": [
                        "plugins/comments/inc/CommentsWidget.php"
                    ],
                    "versions": [
                        {
                            "version": "1.0.0",
                            "lessThanOrEqual": "1.0.0",
                            "status": "affected",
                            "versionType": "custom"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:a:cotonti:cotonti_siena:*:*:*:*:*:*:*:*",
                                    "versionEndIncluding": "1.0.0",
                                    "versionStartIncluding": "1.0.0"
                                }
                            ]
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "format": "CVSS",
                    "cvssV4_0": {
                        "version": "4.0",
                        "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",
                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "attackRequirements": "NONE",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "vulnConfidentialityImpact": "HIGH",
                        "vulnIntegrityImpact": "HIGH",
                        "vulnAvailabilityImpact": "HIGH",
                        "subConfidentialityImpact": "NONE",
                        "subIntegrityImpact": "NONE",
                        "subAvailabilityImpact": "NONE",
                        "baseScore": 9.3,
                        "baseSeverity": "CRITICAL"
                    }
                },
                {
                    "format": "CVSS",
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "scope": "UNCHANGED",
                        "confidentialityImpact": "HIGH",
                        "integrityImpact": "HIGH",
                        "availabilityImpact": "HIGH",
                        "baseScore": 9.8,
                        "baseSeverity": "CRITICAL"
                    }
                }
            ],
            "references": [
                {
                    "url": "https://github.com/Cotonti/Cotonti/issues/1888",
                    "tags": [
                        "issue-tracking"
                    ],
                    "name": "GitHub Issue #1888"
                },
                {
                    "url": "https://github.com/Cotonti/Cotonti/pull/1889",
                    "tags": [
                        "patch",
                        "issue-tracking"
                    ],
                    "name": "Proposed fix PR #1889 (unmerged)"
                },
                {
                    "url": "https://github.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/inc/CommentsWidget.php",
                    "tags": [
                        "technical-description"
                    ],
                    "name": "CommentsWidget::run() at 1.0.0"
                },
                {
                    "url": "https://github.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/controllers/actions/DisplayAction.php",
                    "tags": [
                        "technical-description"
                    ],
                    "name": "AJAX display controller at 1.0.0"
                },
                {
                    "url": "https://github.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/comments.setup.php",
                    "tags": [
                        "technical-description"
                    ],
                    "name": "Default comments permissions at 1.0.0"
                },
                {
                    "url": "https://github.com/Cotonti/Cotonti",
                    "tags": [
                        "product"
                    ]
                },
                {
                    "name": "VulnCheck Advisory: Cotonti 1.0.0 Comments Plugin PHP Object Injection via ci Parameter",
                    "tags": [
                        "third-party-advisory"
                    ],
                    "url": "https://www.vulncheck.com/advisories/cotonti-1.0.0-comments-plugin-php-object-injection-via-ci-parameter"
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "Harsh Raj Singhania",
                    "type": "finder"
                }
            ],
            "x_generator": {
                "engine": "vulncheck-endgame"
            }
        },
        "adp": [
            {
                "references": [
                    {
                        "url": "https://github.com/Cotonti/Cotonti/issues/1888",
                        "tags": [
                            "exploit"
                        ]
                    }
                ],
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-09-16T19:17:38.681650Z",
                                "id": "CVE-2026-91939",
                                "options": [
                                    {
                                        "Exploitation": "poc"
                                    },
                                    {
                                        "Automatable": "yes"
                                    },
                                    {
                                        "Technical Impact": "total"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-09-16T19:18:18.518Z"
                }
            }
        ]
    }
}