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CVE-2021-36369

Published: Oct 12, 2022Updated: May 15, 2025 Sources: CVE List NVD BDU csafCWE-287
NVD MITRE
7.5CVSSHIGH
EPSS Score
1.3%
Top 32.2%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

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 Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:HIntegrity
High
A:NAvailability
None
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Weaknesses

CWE-287

Affected Products

dropbear sshdropbear ssh project
On-prem
Security Products / secure-gateway-vpn
debian linuxdebian
On-premOS
Operating Systems / linux-distro
Dropbear SSHMatt Johnston
On-prem
Communications / email-server-client
n/an/a
dropbear ssh projectoss-projectSecurity Productsaka dropbear ssh
debianoss-projectGBOperating Systemsaka debian gnu/linux
matt johnstonoss-projectCommunicationsaka dropbear ssh

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

2 techniques
Initial Access
View detailed technique mapping

References

https://github.com/mkj/dropbear/pull/128
github.com
https://github.com/mkj/dropbear/releases
github.com
https://github.com/mkj/dropbear/releases/tag/DROPBEAR_2022.82
github.com
and 15 more references View all →

Timeline

Published
Oct 12, 2022
Last Updated
May 15, 2025

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