{"id":"CVE-2026-116844","aliases":["EUVD-2026-110575","GHSA-j2x3-vcc8-r98q"],"status":"published","title":"Fclairamb ftpserverlib through 0.32.4 Cleartext FTPES Data Transfer via PROT P","description":"Fclairamb ftpserverlib through 0.32.4 contains a cleartext transmission vulnerability because TransferOpen checks only the transferTLS flag set by PROT, not whether the prepared data connection uses TLS. When a client sends PROT P after PASV or PORT, file contents and directory listings cross the network unencrypted, even with mandatory encryption, letting on-path attackers read or modify them.","severity":{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.0009,"percentile":0.00409,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-319"],"published":"2026-10-27T00:34:02Z","modified":"2026-10-31T02:30:21Z","products":[{"vendor":"fclairamb","product":"ftpserverlib"},{"vendor":"syncplify, inc.","product":"syncplify server!"}],"references":[{"url":"https://github.com/fclairamb/ftpserverlib/pull/685","tags":["patch","issue-tracking","fix"]},{"url":"https://github.com/fclairamb/ftpserverlib/blob/v0.32.4/handle_misc.go#L29-L31","tags":["technical-description","article"]},{"url":"https://github.com/fclairamb/ftpserverlib/blob/v0.32.4/client_handler.go#L720","tags":["technical-description","article"]},{"url":"https://www.vulncheck.com/advisories/fclairamb-ftpserverlib-through-0.32.4-cleartext-ftpes-data-transfer-via-prot-p","tags":["third-party-advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-116844","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-j2x3-vcc8-r98q"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/116xxx/CVE-2026-116844.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-116844","title":"Fclairamb ftpserverlib through 0.32.4 Cleartext FTPES Data Transfer via PROT P","description":"Fclairamb ftpserverlib through 0.32.4 contains a cleartext transmission vulnerability because TransferOpen checks only the transferTLS flag set by PROT, not whether the prepared data connection uses TLS. When a client sends PROT P after PASV or PORT, file contents and directory listings cross the network unencrypted, even with mandatory encryption, letting on-path attackers read or modify them.","status":"published","published":"2026-10-27T00:34:02.373Z","modified":"2026-10-29T10:52:21.022Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna"},{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-319"],"updated_at":"2026-11-02T14:20:03.4818Z"}],"euvd":[{"id":"EUVD-2026-110575","description":"Fclairamb ftpserverlib through 0.32.4 contains a cleartext transmission vulnerability because TransferOpen checks only the transferTLS flag set by PROT, not whether the prepared data connection uses TLS. When a client sends PROT P after PASV or PORT, file contents and directory listings cross the network unencrypted, even with mandatory encryption, letting on-path attackers read or modify them.","status":"published","published":"2026-10-27T00:34:02Z","modified":"2026-10-29T10:52:21Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-02T16:59:17.279653Z"}],"ghsa":[{"id":"GHSA-j2x3-vcc8-r98q","title":"Fclairamb ftpserverlib through 0.32.4 contains a cleartext transmission vulnerability because...","description":"Fclairamb ftpserverlib through 0.32.4 contains a cleartext transmission vulnerability because TransferOpen checks only the transferTLS flag set by PROT, not whether the prepared data connection uses TLS. When a client sends PROT P after PASV or PORT, file contents and directory listings cross the network unencrypted, even with mandatory encryption, letting on-path attackers read or modify them.","status":"published","published":"2026-10-27T03:32:10Z","modified":"2026-10-27T03:32:19Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"},{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-319"],"updated_at":"2026-11-02T15:14:28.078787Z"}],"nvd":[{"id":"CVE-2026-116844","description":"Fclairamb ftpserverlib through 0.32.4 contains a cleartext transmission vulnerability because TransferOpen checks only the transferTLS flag set by PROT, not whether the prepared data connection uses TLS. When a client sends PROT P after PASV or PORT, file contents and directory listings cross the network unencrypted, even with mandatory encryption, letting on-path attackers read or modify them.","status":"published","published":"2026-10-27T01:19:07.887Z","modified":"2026-10-29T11:17:31.893Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"},{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-319"],"updated_at":"2026-11-02T14:13:03.746397Z"}],"osv":[{"id":"CVE-2026-116844","title":"Fclairamb ftpserverlib through 0.32.4 Cleartext FTPES Data Transfer via PROT P","description":"Fclairamb ftpserverlib through 0.32.4 contains a cleartext transmission vulnerability because TransferOpen checks only the transferTLS flag set by PROT, not whether the prepared data connection uses TLS. When a client sends PROT P after PASV or PORT, file contents and directory listings cross the network unencrypted, even with mandatory encryption, letting on-path attackers read or modify them.","status":"published","published":"2026-10-27T00:34:02.373Z","modified":"2026-10-31T02:30:21.626473073Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-319"],"updated_at":"2026-11-02T15:44:57.008854Z"}]}}