{"cve":"CVE-2021-36368","nvd":{"published":"2022-03-13T00:15:07.937","modified":"2026-06-17T03:58:45.340","status":"Modified","description":"An issue was discovered in OpenSSH before 8.9. If a client is using public-key authentication with agent forwarding but without -oLogLevel=verbose, and an attacker has silently modified the server to support the None authentication option, then the user cannot determine whether FIDO authentication is going to confirm that the user wishes to connect to that server, or that the user wishes to allow that server to connect to a different server on the user's behalf. NOTE: the vendor's position is \"this is not an authentication bypass, since nothing is being bypassed.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","score":3.7},"cwes":["CWE-287"],"references":["https://bugzilla.mindrot.org/show_bug.cgi?id=3316","https://docs.ssh-mitm.at/trivialauth.html","https://github.com/openssh/openssh-portable/pull/258","https://security-tracker.debian.org/tracker/CVE-2021-36368","https://www.openssh.com/security.html"],"products":["debian:debian_linux","openbsd:openssh"],"source":"nvd","synced_at":"2026-10-19T21:29:06.454770966+00:00"},"epss":{"cve":"CVE-2021-36368","score":0.01677,"percentile":0.7689,"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."]}