{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-55107",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-06-16T14:41:54.579Z",
        "datePublished": "2026-09-30T17:06:00.286Z",
        "dateUpdated": "2026-09-30T19:49:04.193Z"
    },
    "containers": {
        "cna": {
            "title": "Kobako Vulnerable to Sandbox Escape: guest eval reaches host RCE via method_missing → public_send (any bound Service)",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-94",
                            "lang": "en",
                            "description": "CWE-94: Improper Control of Generation of Code ('Code Injection')",
                            "type": "CWE"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-470",
                            "lang": "en",
                            "description": "CWE-470: Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection')",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "HIGH",
                        "baseScore": 10,
                        "baseSeverity": "CRITICAL",
                        "confidentialityImpact": "HIGH",
                        "integrityImpact": "HIGH",
                        "privilegesRequired": "NONE",
                        "scope": "CHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/elct9620/kobako/security/advisories/GHSA-7pwq-q9jf-539h",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/elct9620/kobako/security/advisories/GHSA-7pwq-q9jf-539h"
                },
                {
                    "name": "https://github.com/elct9620/kobako/commit/64f84700c81f44902bed9211318d5362f44987b3",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/elct9620/kobako/commit/64f84700c81f44902bed9211318d5362f44987b3"
                },
                {
                    "name": "https://github.com/elct9620/kobako/releases/tag/v0.9.1",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/elct9620/kobako/releases/tag/v0.9.1"
                }
            ],
            "affected": [
                {
                    "vendor": "elct9620",
                    "product": "kobako",
                    "versions": [
                        {
                            "version": ">= 0.1.0, < 0.9.1",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-09-30T17:06:00.286Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Kobako is a Ruby gem that embeds a Wasm-isolated mruby interpreter inside applications, allowing execution of untrusted Ruby scripts (LLM-generated code, user formulas, student submissions, third-party plugins) in-process without giving them access to host memory, files, network, or credentials. From version 0.1.0 to before version 0.9.1, a guest mruby script running inside the Kobako sandbox can execute arbitrary Ruby in the host process, fully escaping the sandbox. This issue has been patched in version 0.9.1."
                }
            ],
            "source": {
                "advisory": "GHSA-7pwq-q9jf-539h",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "references": [
                    {
                        "url": "https://github.com/elct9620/kobako/security/advisories/GHSA-7pwq-q9jf-539h",
                        "tags": [
                            "exploit"
                        ]
                    }
                ],
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-09-30T19:48:55.982496Z",
                                "id": "CVE-2026-55107",
                                "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": "2026-09-30T19:49:04.193Z"
                }
            }
        ]
    }
}