Bug 2509447 - CVE-2026-39831 hcloud: golang.org/x/crypto/ssh: Security key bypass due to missing user presence check [fedora-all]
Summary: CVE-2026-39831 hcloud: golang.org/x/crypto/ssh: Security key bypass due to mi...
Keywords:
Status: ON_QA
Alias: None
Product: Fedora
Classification: Fedora
Component: hcloud
Version: 45
Hardware: Unspecified
OS: Unspecified
high
high
Target Milestone: ---
Assignee: Mikel Olasagasti Uranga
QA Contact:
URL:
Whiteboard: {"flaws": ["1537af73-e36d-4a46-a18e-3...
Depends On:
Blocks: CVE-2026-39831
TreeView+ depends on / blocked
 
Reported: 2026-07-30 14:32 UTC by Guilherme de Almeida Suckevicz
Modified: 2026-08-21 06:01 UTC (History)
3 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Type: ---
Embargoed:


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Description Guilherme de Almeida Suckevicz 2026-07-30 14:32:24 UTC
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.

The Verify() method for FIDO/U2F security key types (sk-ecdsa-sha2-nistp256, sk-ssh-ed25519) did not check the User Presence flag. Signatures generated without physical touch were accepted, allowing unattended use of a hardware security key. To restore the previous behavior, return a "no-touch-required" extension in Permissions.Extensions from PublicKeyCallback.

Comment 1 Aoife Moloney 2026-08-17 15:43:24 UTC
This bug appears to have been reported against 'rawhide' during the Fedora Linux 45 development cycle.
Changing version to 45.

Comment 2 Fedora Update System 2026-08-20 15:13:28 UTC
FEDORA-2026-dd9ec8b0c2 (hcloud-1.67.0-1.fc44) has been submitted as an update to Fedora 44.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-dd9ec8b0c2

Comment 3 Fedora Update System 2026-08-20 15:13:43 UTC
FEDORA-2026-b661d1a235 (hcloud-1.67.0-1.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-b661d1a235

Comment 4 Fedora Update System 2026-08-21 05:42:26 UTC
FEDORA-2026-dd9ec8b0c2 has been pushed to the Fedora 44 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-dd9ec8b0c2`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-dd9ec8b0c2

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

Comment 5 Fedora Update System 2026-08-21 06:01:28 UTC
FEDORA-2026-b661d1a235 has been pushed to the Fedora 43 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-b661d1a235`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-b661d1a235

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


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