Bug 2218212 (CVE-2023-33952, ZDI-23-708, ZDI-CAN-20292)

Summary:	CVE-2023-33952 kernel: vmwgfx: double free within the handling of vmw_buffer_object objects
Product:	[Other] Security Response	Reporter:	Mauro Matteo Cascella <mcascell>
Component:	vulnerability	Assignee:	Nobody <nobody>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	acaringi, allarkin, bhu, chwhite, dbohanno, ddepaula, debarbos, dfreiber, dvlasenk, ezulian, hkrzesin, jarod, jburrell, jdenham, jfaracco, jferlan, jforbes, jlelli, joe.lawrence, jshortt, jstancek, jwyatt, kcarcia, kernel-mgr, ldoskova, lgoncalv, lleshchi, lzampier, nmurray, ptalbert, qzhao, rogbas, rrobaina, rvrbovsk, rysulliv, scweaver, swood, tyberry, vkumar, walters, wcosta, williams, wmealing, ycote, ymankad
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	kernel 6.4-rc1	Doc Type:	---
Doc Text:	A double-free vulnerability was found in the vmwgfx driver in the Linux kernel. The flaw exists within the handling of vmw_buffer_object objects. The issue results from the lack of validating the existence of an object prior to performing further free operations on the object. This flaw allows a local privileged user to escalate privileges and execute code in the context of the kernel.	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:
Bug Depends On:	2218214, 2218215, 2218216, 2218217
Bug Blocks:	2218114

Description Mauro Matteo Cascella 2023-06-28 13:09:03 UTC

A double free vulnerability was found in the vmwgfx driver in the Linux kernel. Quoting ZDI security advisory [1]:

"This vulnerability allows local attackers to escalate privileges on affected installations of Linux Kernel. An attacker must first obtain the ability to execute high-privileged code on the target system in order to exploit this vulnerability.

The specific flaw exists within the handling of vmw_buffer_object objects. The issue results from the lack of validating the existence of an object prior to performing further free operations on the object. An attacker can leverage this vulnerability to escalate privileges and execute code in the context of the kernel."

[1] https://www.zerodayinitiative.com/advisories/ZDI-CAN-20292/

Comment 1 Mauro Matteo Cascella 2023-06-28 13:10:48 UTC

Upstream fix:
https://github.com/torvalds/linux/commit/9ef8d83

Note that the same commit fixed both this issue and CVE-2023-33951 (bug 2218195).