Bug 2494445

Summary:	CVE-2026-39833 docker-buildkit: golang.org/x/crypto/ssh/agent: Security bypass due to unenforced key confirmation [fedora-all]
Product:	[Fedora] Fedora	Reporter:	jkelly <jkelly>
Component:	docker-buildkit	Assignee:	Brad Smith <bradley.g.smith>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	rawhide	CC:	bradley.g.smith, go-sig, maxwell
Target Milestone:	---	Keywords:	Security, SecurityTracking
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:	{"flaws": ["28ae1c3c-f791-4399-96eb-f6f0b2d222a4"]}
Fixed In Version:		Doc Type:	---
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2026-07-16 17:45:30 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:	2480683

Description jkelly 2026-06-29 15:35:40 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 in-memory keyring returned by NewKeyring() silently accepted keys with the ConfirmBeforeUse constraint but never enforced it. The key would sign without any confirmation prompt, with no indication to the caller that the constraint was not in effect. NewKeyring() now returns an error when unsupported constraints are requested.

Comment 1 Brad Smith 2026-07-16 17:45:30 UTC

buildkit [ v0.31.2]
❯ go mod why -m golang.org/x/crypto/ssh/agent
# golang.org/x/crypto/ssh/agent
(main module does not need module golang.org/x/crypto/ssh/agent)