Bug 2555179 (CVE-2026-98755)

Summary:	CVE-2026-98755 kernel: tty: vcc: zero-initialize control packet in vcc_send_ctl()
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
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
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in the Linux kernel's Virtual Console Concentrator (VCC) driver. When sending control messages across a Logical Domain Channel (LDC), the driver transmits packets without completely clearing the allocated memory buffer first. A connected peer can inspect these messages to access uninitialized kernel stack memory, leading to an information disclosure of sensitive system data.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
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Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-10-18 15:59:13 UTC

In the Linux kernel, the following vulnerability has been resolved:

tty: vcc: zero-initialize control packet in vcc_send_ctl()

The stack-allocated struct vio_vcc pkt was partially initialized,
leaving the tag.stype_env field uninitialized before being sent via
ldc_write(), potentially leaking kernel stack data to the LDC peer.

Comment 1 Mauro Matteo Cascella 2026-10-23 03:47:06 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98755.mbox