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{"bugzilla": {"description": "libssh2: libssh2: Heap buffer overflow via integer overflow in publickey attribute allocation", "id": "2493955", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2493955"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H", "status": "draft"}, "cwe": "CWE-787", "details": ["libssh2 through 1.11.1 reads an attacker-controlled 32-bit attribute count from a publickey-subsystem response and uses it in the allocation num_attrs * sizeof(libssh2_publickey_attribute) without bounds checking, so on 32-bit platforms the multiplication overflows to an undersized buffer. A malicious SSH server can then drive the attribute-parsing loop to write past the allocation, causing a heap buffer overflow in a connecting libssh2 client.", "A flaw in libssh2 allows a malicious SSH server to trigger a memory overflow by sending a manipulated attribute count. This can cause the connecting client to crash or allow unauthorized code execution."], "mitigation": {"lang": "en:us", "value": "To mitigate this issue,ensure your applications are running strictly on 64-bit architectures, which naturally prevents the integer overflow from occurring. Additionally, configure your applications to connect only to trusted, verified SSH servers."}, "name": "CVE-2026-58050", "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"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "impact": "moderate", "package_name": "libssh2", "product_name": "Red Hat Hardened Images"}], "public_date": "2026-06-28T01:32:53Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-58050\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-58050\nhttps://github.com/bikini/exploitarium/tree/main/libssh2-publickey-list-calc-poc\nhttps://github.com/libssh2/libssh2/blob/master/src/publickey.c\nhttps://www.vulncheck.com/advisories/libssh2-integer-overflow-in-publickey-subsystem-attribute-allocation"], "statement": "This Moderate impact flaw in libssh2 allows a malicious SSH server to trigger a heap buffer overflow in a connecting client. By manipulating the publickey-subsystem response, an attacker could cause an integer overflow, potentially leading to denial of service or arbitrary code execution on Red Hat systems using libssh2 to establish SSH connections.\nNote: Red Hat Enterprise Linux (RHEL) 8 and newer are not affected by this flaw, as they do not ship the libssh2 package.", "threat_severity": "Moderate"}

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