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{"affected_release": [{"advisory": "RHSA-2026:46927", "cpe": "cpe:/a:redhat:hummingbird:1", "impact": "important", "package": "libssh2-main-1.11.1-10.2.hum1", "product_name": "Red Hat Hardened Images", "release_date": "2026-07-27T00:00:00Z"}], "bugzilla": {"description": "libssh2: libssh2: Information disclosure and potential arbitrary code execution via heap out-of-bounds read", "id": "2506860", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2506860"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.9", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:H", "status": "verified"}, "cwe": "CWE-125", "details": ["A missing bounds check in the libssh2 publickey subsystem allows malicious SSH servers to trigger a client-side out-of-bounds read, leaking heap pointers that could enable security bypasses, denial of service, or code execution."], "mitigation": {"lang": "en:us", "value": "To mitigate this, strictly avoid connecting to untrusted SSH servers and enforce this policy using outbound network firewalls to block unknown IP addresses. For defense-in-depth, utilize OS-level memory protections and service sandboxing to contain any accidental exposure."}, "name": "CVE-2026-66034", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "libssh2", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "libssh2", "product_name": "Red Hat Enterprise Linux 7"}], "public_date": "2026-07-24T16:42:18Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-66034\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-66034\nhttps://github.com/libssh2/libssh2/commit/a13bb6c773f0d55ad1628cede57e99803cd898d9\nhttps://github.com/libssh2/libssh2/pull/2202\nhttps://www.vulncheck.com/advisories/libssh2-heap-out-of-bounds-read-via-publickey-subsystem"], "statement": "This Moderate impact flaw in libssh2 allows a malicious SSH server to trigger an out-of-bounds read on a connecting client. While requiring user interaction to connect to a compromised server and having high attack complexity, successful exploitation could leak heap pointers, potentially aiding in ASLR bypass and leading to arbitrary code execution or denial of service on Red Hat Hardened Images.", "threat_severity": "Moderate"}

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