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Bug 2250331

Summary: CVE-2023-46446 python-asyncssh: Rogue Session Attack [fedora-all]
Product: [Fedora] Fedora Reporter: Borja Tarraso <btarraso>
Component: python-asyncsshAssignee: Georg Sauthoff <fedora>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: high Docs Contact:
Priority: high    
Version: 38CC: fedora, ktdreyer
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: python-asyncssh-2.14.1-1.fc39 Doc Type: No Doc Update
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2023-11-26 01:55:30 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:    
Bug Blocks: 2250329    

Description Borja Tarraso 2023-11-17 18:22:56 UTC
More information about this security flaw is available in the following bug:

http://bugzilla.redhat.com/show_bug.cgi?id=2250329

Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

Comment 1 Borja Tarraso 2023-11-17 18:22:58 UTC
Use the following template to for the 'fedpkg update' request to submit an
update for this issue as it contains the top-level parent bug(s) as well as
this tracking bug.  This will ensure that all associated bugs get updated
when new packages are pushed to stable.

=====

# bugfix, security, enhancement, newpackage (required)
type=security

# low, medium, high, urgent (required)
severity=high

# testing, stable
request=testing

# Bug numbers: 1234,9876
bugs=2250329,2250331

# Description of your update
notes=Security fix for [PUT CVEs HERE]

# Enable request automation based on the stable/unstable karma thresholds
autokarma=True
stable_karma=3
unstable_karma=-3

# Automatically close bugs when this marked as stable
close_bugs=True

# Suggest that users restart after update
suggest_reboot=False

======

Additionally, you may opt to use the bodhi web interface to submit updates:

https://bodhi.fedoraproject.org/updates/new

Comment 2 Fedora Update System 2023-11-17 21:57:49 UTC
FEDORA-2023-d2956318e4 has been submitted as an update to Fedora 39. https://bodhi.fedoraproject.org/updates/FEDORA-2023-d2956318e4

Comment 3 Georg Sauthoff 2023-11-17 22:14:18 UTC
Regarding Fedora 37 and 38:

Unfortunately, asyncssh 2.14.1 requires python3-cryptography >= 39 because it uses the unsafe_skip_rsa_key_validation argument:

https://cryptography.io/en/latest/hazmat/primitives/asymmetric/rsa/#cryptography.hazmat.primitives.asymmetric.rsa.RSAPrivateNumbers.private_key

https://asyncssh.readthedocs.io/en/latest/changes.html#release-2-14-0-30-sep-2023


I'm not sure if there is a good workaround.

Sure, I'm not worried about f37, because it's EOL soon, anyways, but f38.


We might patch 2.14.1 such that that argument is simply not passed along here:

https://github.com/ronf/asyncssh/blob/e9e95aed50b10a54d5f69ca8bc055b40cc880ae8/asyncssh/crypto/rsa.py#L108

However, this would conflict with the upstream documentation and would make certain operations slower, cf.:

https://github.com/ronf/asyncssh/commit/e70969f32257a9ee4002f5c33a91a6d2b34b18dc

Comment 4 Fedora Update System 2023-11-18 02:41:52 UTC
FEDORA-2023-d2956318e4 has been pushed to the Fedora 39 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2023-d2956318e4`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2023-d2956318e4

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 5 Fedora Update System 2023-11-26 01:55:30 UTC
FEDORA-2023-d2956318e4 has been pushed to the Fedora 39 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 6 Georg Sauthoff 2023-11-26 12:51:16 UTC
FWIW, the build logs of the F37/F38 builds that fail due to too old python-cryptography, as described above:

https://koji.fedoraproject.org/koji/taskinfo?taskID=109172662
https://koji.fedoraproject.org/koji/taskinfo?taskID=109173314