Bug 2532203 (CVE-2026-89733)

Summary:	CVE-2026-89733 kernel: usb: gadget: uvc: fix dangling pointers in uvc_function_bind() and uvc_function_unbind()
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:	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 USB Video Class (UVC) gadget driver. This vulnerability occurs in the `uvc_function_bind()` and `uvc_function_unbind()` functions, where pointers to freed memory are not properly cleared. This can lead to a use-after-free (UAF) condition, potentially allowing an attacker to corrupt memory, which may result in a denial of service or arbitrary code execution.	Story Points:	---
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Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-09-11 21:19:31 UTC

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

usb: gadget: uvc: fix dangling pointers in uvc_function_bind() and uvc_function_unbind()

In uvc_function_bind() error path, we use usb_ep_free_request which
uses uvc->control_req but does not set it to NULL afterwards. Thus,
uvc->control_req is a dangling pointer causing a UAF. Also we do not set
the uvc->control_buf pointer to NULL after freeing it, which is another
dangling pointer. Fix it by setting uvc->control_req to NULL after we run
usb_ep_free_request() and uvc->control_buf to NULL after kfree. Do the
same for uvc_function_unbind().

Comment 1 Keith Grant 2026-09-21 15:42:14 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89733.mbox