Bug 2530812 - CVE-2026-78662 complyctl: golang.org/x/crypto/ssh: Denial of Service via channel request flooding [fedora-all]
Summary: CVE-2026-78662 complyctl: golang.org/x/crypto/ssh: Denial of Service via chan...
Keywords:
Status: CLOSED NEXTRELEASE
Alias: None
Product: Fedora
Classification: Fedora
Component: complyctl
Version: rawhide
Hardware: Unspecified
OS: Unspecified
medium
medium
Target Milestone: ---
Assignee: Marcus Burghardt
QA Contact:
URL:
Whiteboard: {"flaws": ["e558e301-1905-4049-a2bf-4...
Depends On:
Blocks: CVE-2026-78662
TreeView+ depends on / blocked
 
Reported: 2026-09-09 12:15 UTC by jkelly
Modified: 2026-10-05 09:44 UTC (History)
3 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed: 2026-10-05 09:44:52 UTC
Type: ---
Embargoed:


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Description jkelly 2026-09-09 12:15:20 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 Marcus Burghardt 2026-09-10 11:11:39 UTC
Same assessment as BZ 2530645. complyctl vendors golang.org/x/crypto v0.55.0 indirectly, but the only usage of the ssh subpackage is for public key fingerprint generation (ssh.NewPublicKey, ssh.FingerprintSHA256). The vulnerable SSH channel/mux code paths (Dial, NewClientConn, NewControlClientConn, NewServerConn) are unreachable — complyctl never opens SSH connections. The flaw is not exploitable. A dependency bump to golang.org/x/crypto >= v0.56.0 will be included in a forthcoming update.

Comment 2 Marcus Burghardt 2026-09-25 10:15:18 UTC
PR proposed in Upstream: https://github.com/complytime/complyctl/pull/884

Comment 3 Marcus Burghardt 2026-10-05 09:44:52 UTC
Fixes merged and included in v1.1.0: https://github.com/complytime/complyctl/releases/tag/v1.1.0


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