CVE-2021-36369

An issue was discovered in Dropbear through 2020.81. Due to a non-RFC-compliant check of the available authentication methods in the client-side SSH code, it is possible for an SSH server to change the login process in its favor. This attack can bypass additional security measures such as FIDO2 tokens or SSH-Askpass. Thus, it allows an attacker to abuse a forwarded agent for logging on to another server unnoticed.

CVSS v3.0 7.5 HIGH

7.5^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/mkj/dropbear/pull/128	Third Party Advisory
https://github.com/mkj/dropbear/releases/tag/DROPBEAR_2022.82	Release Notes Third Party Advisory
https://github.com/mkj/dropbear/releases	Release Notes Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/11/msg00015.html	Mailing List Third Party Advisory

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Configurations

Configuration 1 (hide)

cpe:2.3:a:dropbear_ssh_project:dropbear_ssh:*:*:*:*:*:*:*:*

Configuration 2 (hide)

cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

Information

Published : 2022-10-12 14:15

Updated : 2023-01-20 05:31

NVD link : CVE-2021-36369

Mitre link : CVE-2021-36369

JSON object : View

CWE

CWE-287

Improper Authentication

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Products Affected

debian

debian_linux

dropbear_ssh_project

dropbear_ssh

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