{"cve":"CVE-2020-16171","nvd":{"published":"2020-09-21T14:15:13.370","modified":"2026-06-17T02:57:49.763","status":"Modified","description":"An issue was discovered in Acronis Cyber Backup before 12.5 Build 16342. Some API endpoints on port 9877 under /api/ams/ accept an additional custom Shard header. The value of this header is afterwards used in a separate web request issued by the application itself. This can be abused to conduct SSRF attacks against otherwise unreachable Acronis services that are bound to localhost such as the NotificationService on 127.0.0.1:30572.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","score":6.5},"cwes":["CWE-918"],"references":["http://seclists.org/fulldisclosure/2020/Sep/33","https://www.rcesecurity.com/2020/09/CVE-2020-16171-Exploiting-Acronis-Cyber-Backup-for-Fun-and-Emails/","http://seclists.org/fulldisclosure/2020/Sep/33","https://www.rcesecurity.com/2020/09/CVE-2020-16171-Exploiting-Acronis-Cyber-Backup-for-Fun-and-Emails/"],"products":["acronis:cyber_backup"],"source":"nvd","synced_at":"2026-10-19T21:09:53.489947993+00:00"},"epss":{"cve":"CVE-2020-16171","score":0.05505,"percentile":0.92794,"date":"2026-10-31"},"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."]}