Bug 2553039 (CVE-2026-110929)

Summary:	CVE-2026-110929 openssh: openssh: post-authentication process retains root without file-descriptor passing
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers, yguenane
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
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Doc Text:	A flaw was found in OpenSSH. On platforms that cannot pass file descriptors and that need root to allocate a terminal, the post-authentication session process keeps root privilege. An authenticated user can then perform actions as root, including privileged socket connections and binding forwards to low-numbered ports.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-10-15 04:31:48 UTC

A flaw was found in OpenSSH sshd on platforms that do not support file-descriptor passing and that require root to allocate a PTY. After authentication, the sshd-session process keeps running as root instead of dropping to the logged-in user. That process can then act as root, including connecting to Unix-domain sockets and binding remote forwards to low-numbered TCP ports. Affected platforms are QNX 6, SCO OpenServer 5, and builds configured with --disable-fd-passing. OpenSSH 10.6 disables GatewayPorts and StreamLocalForwarding on those platforms and removes --disable-fd-passing. On Linux, privilege separation drops to the logged-in user, so Red Hat Enterprise Linux is not affected. Reserve the CVE for upstream. Do not file RHEL trackers.