{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-56740",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-06-22T19:17:28.959Z",
        "datePublished": "2026-07-17T21:17:03.239Z",
        "dateUpdated": "2026-07-20T13:58:00.902Z"
    },
    "containers": {
        "cna": {
            "title": "JLine: Unauthenticated Remote Memory Exhaustion via Unbounded Telnet NEW-ENVIRON Variables",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-400",
                            "lang": "en",
                            "description": "CWE-400: Uncontrolled Resource Consumption",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "HIGH",
                        "baseScore": 7.5,
                        "baseSeverity": "HIGH",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "NONE",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/jline/jline3/security/advisories/GHSA-47qp-hqvx-6r3f",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/jline/jline3/security/advisories/GHSA-47qp-hqvx-6r3f"
                },
                {
                    "name": "https://github.com/jline/jline3/pull/2000",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/jline/jline3/pull/2000"
                },
                {
                    "name": "https://github.com/jline/jline3/pull/2001",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/jline/jline3/pull/2001"
                },
                {
                    "name": "https://github.com/jline/jline3/commit/0389f0ee6d0375901b602671ad5dafd4d1d4ee09",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/jline/jline3/commit/0389f0ee6d0375901b602671ad5dafd4d1d4ee09"
                },
                {
                    "name": "https://github.com/jline/jline3/commit/4ee3a73849ffb9a85ec748e4e8cd8f6d81f84f40",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/jline/jline3/commit/4ee3a73849ffb9a85ec748e4e8cd8f6d81f84f40"
                },
                {
                    "name": "https://github.com/jline/jline3/commit/934f09e6128cee33c2b13d42b6e859c1ee2d194b",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/jline/jline3/commit/934f09e6128cee33c2b13d42b6e859c1ee2d194b"
                },
                {
                    "name": "https://github.com/jline/jline3/releases/tag/4.0.16",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/jline/jline3/releases/tag/4.0.16"
                },
                {
                    "name": "https://github.com/jline/jline3/releases/tag/4.2.1",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/jline/jline3/releases/tag/4.2.1"
                },
                {
                    "name": "https://github.com/jline/jline3/releases/tag/jline-3.30.14",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/jline/jline3/releases/tag/jline-3.30.14"
                }
            ],
            "affected": [
                {
                    "vendor": "jline",
                    "product": "jline3",
                    "versions": [
                        {
                            "version": "< 3.30.14",
                            "status": "affected"
                        },
                        {
                            "version": ">= 4.0.0, < 4.0.16",
                            "status": "affected"
                        },
                        {
                            "version": ">= 4.1.0, < 4.2.1",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-07-17T21:17:03.239Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "JLine is a Java library for handling console input. Prior to 3.30.14, 4.0.16, and 4.2.1, the JLine3 Telnet server remote-telnet module does not limit the number of environment variables a client may inject via the Telnet NEW-ENVIRON option, and TelnetIO.readNEVariables() in TelnetIO.java:1127-1180 stores each variable pair in a HashMap held by ConnectionData, allowing an unauthenticated attacker to flood unique variable pairs before the terminating IAC SE byte and exhaust JVM heap memory with an OutOfMemoryError. This issue is fixed in versions 3.30.14, 4.0.16, and 4.2.1."
                }
            ],
            "source": {
                "advisory": "GHSA-47qp-hqvx-6r3f",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "references": [
                    {
                        "url": "https://github.com/jline/jline3/security/advisories/GHSA-47qp-hqvx-6r3f",
                        "tags": [
                            "exploit"
                        ]
                    }
                ],
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-07-20T13:57:48.412665Z",
                                "id": "CVE-2026-56740",
                                "options": [
                                    {
                                        "Exploitation": "poc"
                                    },
                                    {
                                        "Automatable": "yes"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-07-20T13:58:00.902Z"
                }
            }
        ]
    }
}