PT-2022-10510 · Openssh+3 · Openssh+3

Manfred-Kaiser

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Published

2022-03-12

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Updated

2025-11-21

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CVE-2021-36368

CVSS v3.1

3.7

Low

VectorAV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
Name of the Vulnerable Software and Affected Versions OpenSSH versions prior to 8.9
Description An issue was discovered in OpenSSH where a client using public-key authentication with agent forwarding but without -oLogLevel=verbose may be unable to determine whether FIDO authentication is confirming a connection to the intended server or allowing the server to connect to a different server on the user's behalf, if an attacker has silently modified the server to support the None authentication option.
Recommendations For versions prior to 8.9, update to version 8.9 or later to resolve the issue. As a temporary workaround, consider using -oLogLevel=verbose to increase logging and potentially detect such modifications. Restrict access to the server and limit agent forwarding to minimize the risk of exploitation.

Exploit

Fix

Improper Authentication

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Weakness Enumeration

Related Identifiers

ALT-PU-2023-4460
ALT-PU-2024-7269
ALT-PU-2024-9513
AZL-9045
BDU:2025-10810
CVE-2021-36368

Affected Products

Alt Linux
Debian
Openssh
Red Os