{"cve":"CVE-2021-26560","nvd":{"published":"2021-02-26T22:15:19.643","modified":"2026-06-17T03:43:28.690","status":"Modified","description":"Cleartext transmission of sensitive information vulnerability in synoagentregisterd in Synology DiskStation Manager (DSM) before 6.2.3-25426-3 allows man-in-the-middle attackers to spoof servers via an HTTP session.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","score":7.4},"cwes":["CWE-319"],"references":["https://www.synology.com/security/advisory/Synology_SA_20_26","https://www.talosintelligence.com/vulnerability_reports/TALOS-2020-1159","https://www.synology.com/security/advisory/Synology_SA_20_26","https://www.talosintelligence.com/vulnerability_reports/TALOS-2020-1159"],"products":["synology:diskstation_manager","synology:diskstation_manager_unified_controller","synology:skynas_firmware","synology:vs960hd_firmware"],"source":"nvd","synced_at":"2026-10-19T21:15:50.279857260+00:00"},"epss":{"cve":"CVE-2021-26560","score":0.00766,"percentile":0.55506,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}