CVE-2021-36368

** DISPUTED ** 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 v3.0 3.7 LOW
CVSS v2.0 2.6 LOW

3.7^/10

CVSS v3.0 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

2.6^/10

CVSS v2.0 : LOW

Vector : AV:N/AC:H/Au:N/C:P/I:N/A:N

Exploitability : 4.9 / Impact : 2.9

Access Vector NETWORK

Access Complexity HIGH

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact NONE

Availability Impact NONE

References

Link	Resource
https://github.com/openssh/openssh-portable/pull/258	Patch Third Party Advisory
https://docs.ssh-mitm.at/trivialauth.html	Third Party Advisory
https://bugzilla.mindrot.org/show_bug.cgi?id=3316	Issue Tracking Third Party Advisory
https://www.openssh.com/security.html	Vendor Advisory
https://security-tracker.debian.org/tracker/CVE-2021-36368	Third Party Advisory

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Configurations

Configuration 1 (hide)

cpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:*

Configuration 2 (hide)

OR	cpe:2.3:o:debian:debian_linux:9.0:::::::*
	cpe:2.3:o:debian:debian_linux:10.0:::::::*
	cpe:2.3:o:debian:debian_linux:11.0:::::::*

Information

Published : 2022-03-12 16:15

Updated : 2022-07-01 10:21

NVD link : CVE-2021-36368

Mitre link : CVE-2021-36368

JSON object : View

CWE

CWE-287

Improper Authentication

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Products Affected

debian

debian_linux

openbsd

openssh

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