{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-54590",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-06-15T19:45:23.538Z",
        "datePublished": "2026-07-08T20:36:45.258Z",
        "dateUpdated": "2026-07-10T15:00:21.849Z"
    },
    "containers": {
        "cna": {
            "title": "AsyncSSH AuthorizedKeysFile username substitution bypass through ~ and environment expansion",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-22",
                            "lang": "en",
                            "description": "CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')",
                            "type": "CWE"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-639",
                            "lang": "en",
                            "description": "CWE-639: Authorization Bypass Through User-Controlled Key",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "HIGH",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "NONE",
                        "baseScore": 5.9,
                        "baseSeverity": "MEDIUM",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "HIGH",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/ronf/asyncssh/security/advisories/GHSA-qr67-gv47-xwwh",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/ronf/asyncssh/security/advisories/GHSA-qr67-gv47-xwwh"
                },
                {
                    "name": "https://github.com/ronf/asyncssh/commit/3d515ba9ba0cd9990d248bdf62bcf05d51261a88",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/ronf/asyncssh/commit/3d515ba9ba0cd9990d248bdf62bcf05d51261a88"
                },
                {
                    "name": "https://github.com/ronf/asyncssh/releases/tag/v2.23.1",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/ronf/asyncssh/releases/tag/v2.23.1"
                }
            ],
            "affected": [
                {
                    "vendor": "ronf",
                    "product": "asyncssh",
                    "versions": [
                        {
                            "version": "< 2.23.1",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-07-08T20:36:45.258Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "AsyncSSH is a Python package which provides an asynchronous client and server implementation of the SSHv2 protocol on top of the Python asyncio framework. Version 2.23.0 contains an incomplete fix for CVE-2026-45309 in SSHServerConfig._set_tokens that blocks /, , and .. before %u substitution in AuthorizedKeysFile but does not block a leading ~ or ${ENV}, allowing later expansion in _expand_val and Path(filename).expanduser() to escape the intended authorized-keys directory. This issue is fixed in version 2.23.1."
                }
            ],
            "source": {
                "advisory": "GHSA-qr67-gv47-xwwh",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "references": [
                    {
                        "url": "https://github.com/ronf/asyncssh/security/advisories/GHSA-qr67-gv47-xwwh",
                        "tags": [
                            "exploit"
                        ]
                    }
                ],
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-07-10T15:00:13.292812Z",
                                "id": "CVE-2026-54590",
                                "options": [
                                    {
                                        "Exploitation": "poc"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "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": "2026-07-10T15:00:21.849Z"
                }
            }
        ]
    }
}