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Bug 2093897 - SHA1 is used as a proof of possession for the RSA key
Summary: SHA1 is used as a proof of possession for the RSA key
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 8
Classification: Red Hat
Component: openssh
Version: 8.6
Hardware: Unspecified
OS: Unspecified
medium
medium
Target Milestone: rc
: ---
Assignee: Zoltan Fridrich
QA Contact: Ondrej Moriš
Jan Fiala
URL:
Whiteboard:
: 2060232 (view as bug list)
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2022-06-06 10:15 UTC by Dmitry Belyavskiy
Modified: 2022-11-08 12:47 UTC (History)
6 users (show)

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.
Clone Of:
Environment:
Last Closed: 2022-11-08 10:53:35 UTC
Type: Bug
Target Upstream Version:
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
OpenSSH Project 3375 0 None None None 2022-06-06 10:15:36 UTC
Red Hat Issue Tracker CRYPTO-7483 0 None None None 2022-06-07 13:14:33 UTC
Red Hat Issue Tracker RHELPLAN-124339 0 None None None 2022-06-06 10:21:49 UTC
Red Hat Knowledge Base (Solution) 6816771 0 None None None 2022-06-07 09:05:33 UTC
Red Hat Product Errata RHBA-2022:7763 0 None None None 2022-11-08 10:53:46 UTC

Description Dmitry Belyavskiy 2022-06-06 10:15:37 UTC 
If we need to get a proof of ownership for a RSA key on establishing a connection, the SHA1 algorithm is used by default (see the ssh_rsa_sign function). Not sure that it is the best possible option now. 

As it is possible to explicitly request the hash, it's worth analyze the client's capabilities and use SHA2 for this purpose.

The upstream patch should be applied to RHEL 8 series.
Comment 1 Marek Havrila 2022-06-07 09:05:33 UTC 
*** Bug 2060232 has been marked as a duplicate of this bug. ***
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
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