Bug 1628313

Summary: Recent packages of OpenSSH breaks Certificate Authentication for certain servers
Product: [Fedora] Fedora Reporter: Antonio Dias <accdias>
Component: opensshAssignee: Jakub Jelen <jjelen>
Status: CLOSED DUPLICATE QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: high Docs Contact:
Priority: unspecified    
Version: 28CC: dwalsh, jfch, jjelen, lkundrak, mattias.ellert, plautrba, tmraz
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2018-09-13 07:23:56 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:
Attachments:
Description Flags
ssh -vvvv centos7.5-server output
none
sshd_config on CentOS 7.5 server none

Description Antonio Dias 2018-09-12 18:07:10 UTC
Created attachment 1482807 [details]
ssh -vvvv centos7.5-server output

Description of problem:

I'm using OpenSSH's certificate based authentication without any problem with openssh-7.7p1-2.fc28.x86_64. As soon as I upgrade it to any new package version, authentication starts to fail when connecting a CentOS 7.5 box but it succeed connecting CentOS 6.10.

CentOS 7.5 is using the following OpenSSH package:

- openssh-7.4p1-16.el7.x86_64

CentOS 6.10 is using the following OpenSSH package:

- openssh-5.3p1-123.el6_9.x86_64

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

- Fedora 28 x86_64
- OpenSSH packages after openssh-7.7p1-2.fc28.x86_64

How reproducible:

Always reproducible.


Steps to Reproduce:
1. Using OpenSSH signed certificates, try to connect a remote host running CentOS/RHEL 7.5, configured to just accept certificates authentication, from a Fedora 28 client, using any OpenSSH package higher than openssh-7.7p1-2.fc28.x86_64.


Actual results:

Authentication fails with "Permission denied (publickey,gssapi-keyex,gssapi-with-mic)." message

Expected results:

Authentication succeeds.


Additional info:

Comment 1 Antonio Dias 2018-09-12 18:08:18 UTC
Created attachment 1482809 [details]
sshd_config on CentOS 7.5 server

Comment 2 Antonio Dias 2018-09-12 18:10:39 UTC
The workaround I'm using is 'sudo dnf downgrade -y openssh', which installs openssh-7.7p1-2.fc28.x86_64, version that is working fine.

Comment 3 Jakub Jelen 2018-09-13 07:23:56 UTC

*** This bug has been marked as a duplicate of bug 1627875 ***