{
    "document": {
        "category": "csaf_security_advisory",
        "csaf_version": "2.0",
        "distribution": {
            "tlp": {
                "label": "WHITE"
            }
        },
        "lang": "nl",
        "notes": [
            {
                "category": "legal_disclaimer",
                "text": "The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this page to enhance access to its information and security advisories. The use of this security advisory is subject to the following terms and conditions:\n\n    NCSC-NL makes every reasonable effort to ensure that the content of this page is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or continuous keeping up-to-date. The information contained in this security advisory is intended solely for the purpose of providing general information to professional users. No rights can be derived from the information provided therein.\n\n    NCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of this security advisory. This includes damage resulting from the inaccuracy of incompleteness of the information contained in the advisory.\n    This security advisory is subject to Dutch law. All disputes related to or arising from the use of this advisory will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings."
            },
            {
                "category": "description",
                "text": "Het OpenSSH project heeft een kwetsbaarheid verholpen in sshd van OpenSSH versies ouder dan 10.6p2. De kwetsbaarheid treft Linux systemen die gebruikmaken van musl libc en waarop PAM niet wordt gebruikt.",
                "title": "Feiten"
            },
            {
                "category": "description",
                "text": "De kwetsbaarheid betreft een bypass van de SSH-wachtwoordauthenticatie bij gebruik van wachtwoorden met een lengte van 257 tot 1024 bytes. De oorzaak ligt in de interactie tussen de authenticatieafhandeling van OpenSSH (sshd) en de implementatie van crypt() in musl libc, in omgevingen waarin PAM niet wordt gebruikt. Hierdoor kan een aanvaller onder specifieke omstandigheden de wachtwoordverificatie omzeilen en mogelijk ongeautoriseerde toegang tot het systeem verkrijgen.\n\nMisbruik vereist dat aan meerdere voorwaarden wordt voldaan:\n\n- Het systeem draait Linux met musl libc, zoals Alpine Linux.\n- OpenSSH draait zonder PAM.\n- PasswordAuthentication is ingeschakeld.\n- Er is een account aanwezig met een * als password hash en minimaal één ander account met een geldige SHA-256 of SHA-512 password hash.\n\nDe kwetsbaarheid is daarmee beperkt tot specifieke configuraties. Reguliere Debian en Ubuntu installaties, die gebruikmaken van glibc, vallen buiten het beschreven toepassingsgebied.\n\nVanuit securityoogpunt wordt geadviseerd SSH-beheerdiensten niet rechtstreeks aan het internet bloot te stellen. Beperk de toegang waar mogelijk tot vertrouwde netwerken en schakel wachtwoordauthenticatie uit wanneer deze niet noodzakelijk is.",
                "title": "Interpretaties"
            },
            {
                "category": "description",
                "text": "OpenSSH Project heeft updates uitgebracht om de kwetsbaarheid te verhelpen. Zie bijgevoegde referenties voor meer informatie.",
                "title": "Oplossingen"
            },
            {
                "category": "general",
                "text": "medium",
                "title": "Kans"
            },
            {
                "category": "general",
                "text": "high",
                "title": "Schade"
            },
            {
                "category": "general",
                "text": "Unexpected Status Code or Return Value",
                "title": "CWE-394"
            }
        ],
        "publisher": {
            "category": "coordinator",
            "contact_details": "cert@ncsc.nl",
            "name": "Nationaal Cyber Security Centrum",
            "namespace": "https://www.ncsc.nl/"
        },
        "references": [
            {
                "category": "external",
                "summary": "Reference",
                "url": "https://www.openssh.org/releasenotes.html#10.6p2"
            }
        ],
        "title": "Kwetsbaarheid verholpen in OpenSSH door OpenSSH Project",
        "tracking": {
            "current_release_date": "2026-11-06T07:54:37.219918Z",
            "generator": {
                "date": "2025-08-04T16:30:00Z",
                "engine": {
                    "name": "V.A.",
                    "version": "1.3"
                }
            },
            "id": "NCSC-2026-0469",
            "initial_release_date": "2026-11-06T07:54:37.219918Z",
            "revision_history": [
                {
                    "date": "2026-11-06T07:54:37.219918Z",
                    "number": "1.0.0",
                    "summary": "Initiele versie"
                }
            ],
            "status": "final",
            "version": "1.0.0"
        }
    },
    "product_tree": {
        "branches": [
            {
                "branches": [
                    {
                        "branches": [
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/*",
                                "product": {
                                    "name": "vers:unknown/*",
                                    "product_id": "CSAFPID-1"
                                }
                            }
                        ],
                        "category": "product_name",
                        "name": "OpenSSH"
                    }
                ],
                "category": "vendor",
                "name": "OpenBSD"
            }
        ]
    },
    "vulnerabilities": [
        {
            "cve": "CVE-2026-123158",
            "cwe": {
                "id": "CWE-394",
                "name": "Unexpected Status Code or Return Value"
            },
            "notes": [
                {
                    "category": "other",
                    "text": "Unexpected Status Code or Return Value",
                    "title": "CWE-394"
                },
                {
                    "category": "description",
                    "text": "OpenSSH sshd versions prior to 10.6p2 on Linux systems using musl libc without PAM are vulnerable to a password authentication bypass for passwords between 256 and 1024 characters, notably impacting Alpine Linux.",
                    "title": "Summary"
                }
            ],
            "product_status": {
                "known_affected": [
                    "CSAFPID-1"
                ]
            },
            "references": [
                {
                    "category": "self",
                    "summary": "CVE-2026-123158 | NCSC-NL Website",
                    "url": "https://vulnerabilities.ncsc.nl/csaf/v2/2026/cve-2026-123158.json"
                }
            ],
            "scores": [
                {
                    "cvss_v3": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
                        "baseScore": 8.1,
                        "baseSeverity": "HIGH"
                    },
                    "products": [
                        "CSAFPID-1"
                    ]
                }
            ],
            "title": "CVE-2026-123158"
        }
    ]
}