VMSA-2023-0019

Important

Advisory ID:
VMSA-2023-0019.1

CVSSv3 Range:
7.5

Issue Date:
2023-08-31

Updated On:
2023-09-05

CVE(s):
CVE-2023-20900

Synopsis:
VMware Tools updates address a SAML Token Signature Bypass Vulnerability (CVE-2023-20900)

1. Impacted Products

VMware Tools

2. Introduction

A SAML token signature bypass vulnerability in VMware Tools was responsibly reported to VMware. Updates are available to remediate this vulnerability in the affected VMware products.

3. SAML Token Signature Bypass vulnerability (CVE-2023-20900)

Description

VMware Tools contains a SAML token signature bypass vulnerability. VMware has evaluated the severity of this issue to be in the Important severity range with a maximum CVSSv3 base score of 7.5.

Known Attack Vectors

A malicious actor that has been granted Guest Operation Privileges in a target virtual machine may be able to elevate their privileges if that target virtual machine has been assigned a more privileged Guest Alias.

Resolution

To remediate CVE-2023-20900 apply the patches listed in the ‘Fixed Version’ column of the ‘Response Matrix’ found below.

Workarounds

None.

Additional Documentation

None.

Notes

[1] VMware Tools 10.3.26 only applies to the older Linux releases.
[2] A version of open-vm-tools that addresses CVE-2023-20900 will be distributed by Linux vendors.
[3] Fixed versions may differ based on the Linux distribution version and the distribution vendor.

Acknowledgements

VMware would like to thank Peter Stöckli of GitHub Security Lab for reporting this issue to us.

Response Matrix

Product	Version	Running On	CVE Identifier	CVSSv3	Severity	Fixed Version	Workarounds	Additional Documentation
VMware Tools	12.x.x, 11.x.x, 10.3.x	Windows	CVE-2023-20900	7.5	important	12.3.0	None	None
VMware Tools	10.3.x	Linux	CVE-2023-20900	7.5	important	[1] 10.3.26	None	None
[2] VMware Tools (open-vm-tools)	12.x.x, 11.x.x, 10.3.x	Linux	CVE-2023-20900	7.5	important	[3] 12.3.0	None	None