Bug 2502446 (CVE-2026-63946)

Summary:	CVE-2026-63946 kernel: Bluetooth: ISO: fix UAF in iso_recv_frame
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
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Doc Text:	A flaw was found in the Linux kernel's Bluetooth ISO (Isochronous Stream) subsystem. This vulnerability, known as a Use-After-Free, occurs because the system attempts to use a memory area after it has been released, which can lead to unpredictable behavior. A malicious actor could potentially exploit this flaw to execute unauthorized code, gaining full control over the affected system.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-07-19 16:08:37 UTC

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

Bluetooth: ISO: fix UAF in iso_recv_frame

iso_recv_frame reads conn->sk under iso_conn_lock but releases the lock
before using sk, with no reference held. A concurrent iso_sock_kill()
can free sk in that window, causing use-after-free on sk->sk_state and
sock_queue_rcv_skb().

Fix by replacing the bare pointer read with iso_sock_hold(conn), which
calls sock_hold() while the spinlock is held, atomically elevating the
refcount before the lock drops. Add a drop_put label so sock_put() is
called on all exit paths where the hold succeeded.

Comment 1 Mauro Matteo Cascella 2026-07-21 14:34:47 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026071954-CVE-2026-63946-b5d8@gregkh/T