Bug 2050511

Summary:	Confusing message "Using arbitrary primes is not allowed in FIPS mode. Falling back to known groups" printed on FIPS systems
Product:	Red Hat Enterprise Linux 8	Reporter:	Renaud Métrich <rmetrich>
Component:	openssh	Assignee:	Zoltan Fridrich <zfridric>
Status:	CLOSED ERRATA	QA Contact:	Marek Havrila <mhavrila>
Severity:	low	Docs Contact:
Priority:	low
Version:	8.5	CC:	jjelen, mhavrila, zfridric
Target Milestone:	rc	Keywords:	Triaged
Target Release:	---
Hardware:	All
OS:	All
Whiteboard:
Fixed In Version:	openssh-8.0p1-14.el8	Doc Type:	No Doc Update
Doc Text:	If this bug requires documentation, please select an appropriate Doc Type value.	Story Points:	---
Clone Of:
Clones:	2102201 (view as bug list)		Environment:
Last Closed:	2022-11-08 10:53:35 UTC	Type:	Bug
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:
Bug Blocks:	2102201

Description Renaud Métrich 2022-02-04 08:27:23 UTC

Description of problem:

When a SSH server is configured in FIPS and a SSH client forces using KexAlgorithm=diffie-hellman-group-exchange-sha256, the following message is recorded in the journal:

  Using arbitrary primes is not allowed in FIPS mode. Falling back to known groups.

Talking to Jakub, he agrees this message can be downgraded to verbose since it doesn't have much value from user's point of view.

Version-Release number of selected component (if applicable):

openssh-server-8.0p1-10.el8.x86_64

How reproducible:

Always

Steps to Reproduce:
1. Enable FIPS on the server
2. Connect to server

  $ ssh -o KexAlgorithm=diffie-hellman-group-exchange-sha256 <server>

Comment 9 errata-xmlrpc 2022-11-08 10:53:35 UTC

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (openssh bug fix and enhancement update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2022:7763