{"id":"CVE-2025-15661","state":"PUBLISHED","title":"libssh2 - Heap Buffer Over-read via sftp_symlink() in sftp.c","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 operation.","publishedAt":"2026-06-18T20:18:29.475Z","updatedAt":"2026-09-24T14:17:17.482Z","severity":{"score":8.3,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N","source":"VulnCheck"},"assigner":"VulnCheck","products":["libssh2 libssh2"],"affected":[{"vendor":"libssh2","product":"libssh2","packageURL":"pkg:github/libssh2/libssh2","defaultStatus":"affected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"1.11.1","versionType":"semver"},{"version":"2dae3024897e1898d389835151f4e9606227721d","status":"unaffected","versionType":"git"}],"repo":"https://github.com/libssh2/libssh2"}],"references":["https://github.com/libssh2/libssh2/pull/1705","https://github.com/libssh2/libssh2/pull/1717","https://github.com/libssh2/libssh2/commit/2dae3024897e1898d389835151f4e9606227721d","https://www.vulncheck.com/advisories/libssh2-heap-buffer-over-read-via-sftp-symlink-in-sftp-c"],"weaknesses":["CWE-125"],"ingestedAt":"2026-10-29T20:08:31.050Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/15xxx/CVE-2025-15661.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-15661","state":"PUBLISHED","datePublished":"2026-06-18T20:18:29.475Z","dateUpdated":"2026-09-24T14:17:17.482Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-06-18T20:12:38.095Z"},"containers":{"cna":{"title":"libssh2 - Heap Buffer Over-read via sftp_symlink() in sftp.c","descriptions":[{"lang":"en","value":"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. 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