{"id":"CVE-2026-90869","title":"Pre-Authentication SSH Denial of Service via Malformed Public-Key Signature in Progress WS_FTP Server","summary":"A remote attacker who knows a valid account's enrolled SSH public key can terminate the shared SSH service in Progress Software WS_FTP Server versions prior to 2024.0.7 and 2025.0.4 on Windows.","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cvssSource":"cna","cwe":["CWE-125","CWE-20"],"vendor":"Progress Software","product":"WS_FTP Server","affected":["ws_ftp_server < 2024.0.7","ws_ftp_server < 2025.0.4"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-10-30T17:14:25.359940Z"},"published":"2026-10-29","updated":"2026-10-30","sourceUpdated":"2026-10-30T17:14:35.864Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-90869","references":[{"url":"https://progress.lightning.force.com/lightning/r/Knowledge__kav/ka7Pb000001vl86IAA/view"}],"tags":["cve.org"],"epss":0.00356,"epssPercentile":0.29567,"ingestedAt":"2026-11-05T16:24:31.148Z","slug":"CVE-2026-90869","body":"## Overview\n\nA remote attacker who knows a valid account's enrolled SSH public key can terminate the shared SSH service in Progress Software WS_FTP Server versions prior to 2024.0.7 and 2025.0.4 on Windows.\n\n## Affected\n\n- `ws_ftp_server < 2024.0.7`\n- `ws_ftp_server < 2025.0.4`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n### Workarounds\n\nRestrict network access to the SSH/SFTP service to trusted clients and disable SSH/SFTP access if it is not required. Contact Progress Software Technical Support for guidance on available mitigations.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}