Bug 2530770

Summary: CVE-2026-78662 opkssh: golang.org/x/crypto/ssh: Denial of Service via channel request flooding [fedora-all]
Product: [Fedora] Fedora Reporter: jkelly <jkelly>
Component: opksshAssignee: Till Hofmann <thofmann>
Status: CLOSED ERRATA QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: rawhideCC: go-sig, thofmann
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["e558e301-1905-4049-a2bf-4abd80cf6714"]}
Fixed In Version: opkssh-0.16.0-3.fc45 opkssh-0.16.0-3.fc44 opkssh-0.16.0-3.fc43 Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-09-21 00:15:17 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: 2528026    

Description jkelly 2026-09-09 12:01:22 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.

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection. Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

Comment 1 Fedora Update System 2026-09-12 08:52:33 UTC
FEDORA-2026-38b019a0f0 (opkssh-0.16.0-3.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-38b019a0f0

Comment 2 Fedora Update System 2026-09-12 08:52:42 UTC
FEDORA-2026-f7b73f165d (opkssh-0.16.0-3.fc44) has been submitted as an update to Fedora 44.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-f7b73f165d

Comment 3 Fedora Update System 2026-09-12 08:52:48 UTC
FEDORA-2026-559bbb39f5 (opkssh-0.16.0-3.fc45) has been submitted as an update to Fedora 45.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-559bbb39f5

Comment 4 Fedora Update System 2026-09-13 18:30:48 UTC
FEDORA-2026-f7b73f165d 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-f7b73f165d`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-f7b73f165d

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

Comment 5 Fedora Update System 2026-09-13 18:46:25 UTC
FEDORA-2026-559bbb39f5 has been pushed to the Fedora 45 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-559bbb39f5`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-559bbb39f5

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

Comment 6 Fedora Update System 2026-09-13 19:13:29 UTC
FEDORA-2026-38b019a0f0 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-2026-38b019a0f0`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-38b019a0f0

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

Comment 7 Fedora Update System 2026-09-21 00:15:17 UTC
FEDORA-2026-559bbb39f5 (opkssh-0.16.0-3.fc45) has been pushed to the Fedora 45 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 8 Fedora Update System 2026-09-21 00:52:00 UTC
FEDORA-2026-f7b73f165d (opkssh-0.16.0-3.fc44) has been pushed to the Fedora 44 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 9 Fedora Update System 2026-09-21 01:04:27 UTC
FEDORA-2026-38b019a0f0 (opkssh-0.16.0-3.fc43) has been pushed to the Fedora 43 stable repository.
If problem still persists, please make note of it in this bug report.