Is CVE-2021-36368 in the CISA KEV catalog?

No. CVE-2021-36368 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2021-36368?

CVE-2021-36368 has a CVSS v3 base score of 3.7 (LOW).

What is the EPSS score for CVE-2021-36368?

CVE-2021-36368 has an EPSS score of 1.68% (74th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2021-36368?

Upgrade openssh on debian 12 to 1:8.9p1-1 or later.

CVE & CISA-KEV Catalog

CVE-2021-36368

LOWEPSS 74th pctl

3.7

CVSS v3

NVD

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.

CWE-287Improper Authentication

How to fix

Remediation Available

opensshDebian

Fixed in:1:8.9p1-1CVE-2021-36368

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityHigh

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityLow

IntegrityNone

AvailabilityNone

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

Exploit Intelligence

1.68%probability of exploitation in 30 days

74thpercentile

Elevated risk: more likely to be exploited than 74% of all known CVEs.

References

Patch1

github.com

Vendor Advisory1

openssh.com

Third-Party Advisory3

Related Vulnerabilities

Other CWE-287 (Improper Authentication) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2023-35082	Critical	9.8	100%	KEV + Ransom	Fix
CVE-2023-35078	Critical	9.8	100%	KEV + Ransom	Fix
CVE-2017-7921	Critical	9.8	100%	KEV	-
CVE-2024-7593	Critical	9.8	100%	KEV	-
CVE-2023-46805	High	8.2	100%	KEV + Ransom	-
CVE-2022-40684	Critical	9.8	100%	KEV + Ransom	Fix

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-05-29.