Bug 2492762 (CVE-2026-53209)

Summary:	CVE-2026-53209 kernel: Bluetooth: hci_sync: reject oversized Broadcast Announcement prepend
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	rhel-process-autobot, 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 Bluetooth subsystem of the Linux kernel, specifically within the `hci_sync` component. This vulnerability occurs when the `hci_adv_bcast_annoucement()` function attempts to prepend Broadcast Announcement service data to an existing advertising payload that is already at its maximum size. This can lead to an oversized data packet that may overrun a temporary buffer, potentially causing a denial of service (DoS) or other unpredictable system behavior.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-06-25 10:04:24 UTC

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

Bluetooth: hci_sync: reject oversized Broadcast Announcement prepend

Existing advertising instances can already hold the maximum extended
advertising payload. When hci_adv_bcast_annoucement() prepends the
Broadcast Announcement service data to that payload, the combined data
may no longer fit in the temporary buffer used to rebuild the
advertising data.

Reject that case before copying the existing payload and report the
failure through the device log. This keeps the existing advertising
data intact and avoids overrunning the temporary buffer.

Comment 1 TEJ RATHI 2026-06-26 09:10:04 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026062502-CVE-2026-53209-92bf@gregkh/T