{"cve":{"cve_id":"CVE-2025-15661","is_kev":false,"kev_date_added":null,"kev_vendor_project":null,"kev_product":null,"kev_vulnerability_name":null,"kev_short_description":null,"kev_required_action":null,"kev_due_date":null,"kev_known_ransomware":null,"kev_notes":null,"kev_cwes":null,"epss_score":0.00267,"epss_percentile":0.18092,"epss_as_of":"2026-06-23","description":"libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy 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System)","value":"N","value_label":"None"}]},"affected":[{"vendor_slug":"libssh2","vendor_name":"libssh2","product_slug":"libssh2","product_name":"libssh2","version_start":"0","version_start_inclusive":true,"version_end":"1.11.1","version_end_inclusive":true,"cpe23_uri":"cve5:libssh2:libssh2:0:1.11.1"},{"vendor_slug":"libssh2","vendor_name":"libssh2","product_slug":"libssh2","product_name":"libssh2","version_start":"2dae3024897e1898d389835151f4e9606227721d","version_start_inclusive":true,"version_end":"2dae3024897e1898d389835151f4e9606227721d","version_end_inclusive":true,"cpe23_uri":"cve5:libssh2:libssh2:2dae3024897e1898d389835151f4e9606227721d:2dae3024897e1898d389835151f4e9606227721d"}],"exploit_refs":[],"news":[],"references":[{"url":"https://github.com/libssh2/libssh2/pull/1705","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/libssh2/libssh2/pull/1717","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/libssh2/libssh2/commit/2dae3024897e1898d389835151f4e9606227721d","source_type":"PATCH","tags":["patch"]},{"url":"https://www.vulncheck.com/advisories/libssh2-heap-buffer-over-read-via-sftp-symlink-in-sftp-c","source_type":"VENDOR_ADVISORY","tags":["advisory"]}],"timeline":[{"type":"published","at":"2026-06-18T20:18:29.475000Z","label":"CVE 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