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{"bugzilla": {"description": "libssh2: libssh2: Information disclosure and denial of service via crafted SFTP response", "id": "2490586", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2490586"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H", "status": "draft"}, "cwe": "CWE-125", "details": ["A flaw in libssh2's sftp_symlink() function allows a malicious SSH server or man-in-the-middle attacker to trigger an out-of-bounds heap read via a crafted SSH_FXP_NAME response. This can disclose heap memory contents or crash the application, causing a denial of service (DoS)."], "mitigation": {"lang": "en:us", "value": "Implement strict network egress filtering to allow outbound SSH/SFTP traffic only to known, trusted endpoints. Additionally, enforce strict SSH host key checking in your libssh2 client applications to reject unknown servers and prevent Man-in-the-Middle (MitM) attacks."}, "name": "CVE-2025-15661", "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": "Out of support scope", "package_name": "libssh2", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "libssh2", "product_name": "Red Hat Hardened Images"}], "public_date": "2026-06-18T20:18:29Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2025-15661\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-15661\nhttps://github.com/libssh2/libssh2/commit/2dae3024897e1898d389835151f4e9606227721d\nhttps://github.com/libssh2/libssh2/pull/1705\nhttps://github.com/libssh2/libssh2/pull/1717\nhttps://www.vulncheck.com/advisories/libssh2-heap-buffer-over-read-via-sftp-symlink-in-sftp-c"], "statement": "This Moderate-impact out-of-bounds heap read flaw in libssh2 allows a malicious SSH server or man-in-the-middle attacker to crash the application (DoS) or disclose heap memory by sending a crafted SFTP response.", "threat_severity": "Moderate"}