Bug 2135229 (CVE-2021-36369)

Summary:	CVE-2021-36369 <net-misc/dropbear-2022.82: forwarded agent abuse
Product:	[Other] Security Response	Reporter:	Marian Rehak <mrehak>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED UPSTREAM	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	buytenh, daniellarasouza, epel-packagers-sig, i
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2022-11-29 20:27:59 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2135230, 2135231
Bug Blocks:

Description Marian Rehak 2022-10-17 06:15:06 UTC

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.

Reference:

https://github.com/mkj/dropbear/pull/128
https://github.com/mkj/dropbear/releases/tag/DROPBEAR_2022.82
https://github.com/mkj/dropbear/releases

Comment 1 Marian Rehak 2022-10-17 06:15:24 UTC

Created dropbear tracking bugs for this issue:

Affects: epel-all [bug 2135231]
Affects: fedora-all [bug 2135230]

Comment 2 Product Security DevOps Team 2022-11-29 20:27:57 UTC

This CVE Bugzilla entry is for community support informational purposes only as it does not affect a package in a commercially supported Red Hat product. Refer to the dependent bugs for status of those individual community products.