CVE-2026-54590

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{"affected": [{"affectedData": [{"product": "asyncssh", "vendor": "ronf", "versions": [{"status": "affected", "version": "< 2.23.1"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "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."}, {"lang": "es", "value": "AsyncSSH es un paquete de Python que proporciona una implementaci\u00f3n as\u00edncrona de cliente y servidor del protocolo SSHv2 sobre el framework asyncio de Python. La versi\u00f3n 2.23.0 contiene una correcci\u00f3n incompleta para CVE-2026-45309 en SSHServerConfig._set_tokens que bloquea /, \\, y .. antes de la sustituci\u00f3n de %u en AuthorizedKeysFile pero no bloquea un ~ inicial o ${ENV}, permitiendo una expansi\u00f3n posterior en _expand_val y Path(filename).expanduser() para escapar del directorio de claves autorizadas previsto. Este problema est\u00e1 corregido en la versi\u00f3n 2.23.1."}], "id": "CVE-2026-54590", "lastModified": "2026-10-25T17:10:00.197", "metrics": {"cvssMetricV31": [{"cvssData": {"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"}, "exploitabilityScore": 2.2, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-54590", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-07-10T15:00:13.292812Z", "version": "2.0.3"}}]}, "published": "2026-07-08T21:16:49.523", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/ronf/asyncssh/commit/3d515ba9ba0cd9990d248bdf62bcf05d51261a88"}, {"source": "security-advisories@github.com", "url": "https://github.com/ronf/asyncssh/releases/tag/v2.23.1"}, {"source": "security-advisories@github.com", "url": "https://github.com/ronf/asyncssh/security/advisories/GHSA-qr67-gv47-xwwh"}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "url": "https://github.com/ronf/asyncssh/security/advisories/GHSA-qr67-gv47-xwwh"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-22"}, {"lang": "en", "value": "CWE-639"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

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