Bug 2129739 (CVE-2022-3165)

Summary:	CVE-2022-3165 QEMU: VNC: integer underflow in vnc_client_cut_text_ext leads to CPU exhaustion
Product:	[Other] Security Response	Reporter:	Mauro Matteo Cascella <mcascell>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	berrange, cfergeau, crobinso, ddepaula, eglynn, jen, jferlan, jjoyce, jmaloy, knoel, lhh, lkundrak, mburns, mcascell, mgarciac, mkenneth, mrezanin, mst, ondrejj, pbonzini, philmd, rjones, spower, virt-maint, virt-maint
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	qemu 7.2.0-rc0	Doc Type:	If docs needed, set a value
Doc Text:	An integer underflow issue was found in the QEMU built-in VNC server while processing ClientCutText messages in the extended format. A malicious client could use this flaw to make QEMU unresponsive by sending a specially crafted payload message, resulting in a denial of service.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2023-05-17 01:43:09 UTC	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:	2129759, 2129760, 2129761
Bug Blocks:	2118918

Description Mauro Matteo Cascella 2022-09-26 08:35:49 UTC

An integer underflow issue was found in the QEMU VNC server while processing ClientCutText messages in the extended format [1]. A malicious client could use this flaw to make QEMU unresponsive by sending a specially crafted payload message, resulting in a denial of service condition.

[1] https://github.com/rfbproto/rfbproto/blob/master/rfbproto.rst#extended-clipboard-pseudo-encoding

Comment 1 Mauro Matteo Cascella 2022-09-26 08:37:56 UTC

Proposed patch:
https://lists.nongnu.org/archive/html/qemu-devel/2022-09/msg03948.html

Comment 2 Mauro Matteo Cascella 2022-09-26 09:26:17 UTC

Created qemu tracking bugs for this issue:

Affects: fedora-all [bug 2129759]

Comment 4 Mauro Matteo Cascella 2022-10-17 08:04:23 UTC

Upstream commit:
https://gitlab.com/qemu-project/qemu/-/commit/d307040b18

Comment 6 errata-xmlrpc 2023-05-09 07:13:05 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2023:2162 https://access.redhat.com/errata/RHSA-2023:2162

Comment 7 errata-xmlrpc 2023-05-16 08:08:18 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2023:2757 https://access.redhat.com/errata/RHSA-2023:2757

Comment 8 Product Security DevOps Team 2023-05-17 01:43:06 UTC

This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):

https://access.redhat.com/security/cve/cve-2022-3165