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CVE-2022-22977NVD status: Modified

VMware Tools for Windows: Improper Restriction of XML External Entity Reference

CVE-2022-22977 is a high-severity improper restriction of XML external entity reference vulnerability in VMware Tools for Windows, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. Affected VMware Tools for Windows versions: VMware Tools for Windows (12.0.0, 11.x.y and 10.x.y). The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.8% chance of exploitation within 30 days, higher than 57% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Tools to 12.0.5 or a later version.
  2. Read the advisory on vmware.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
VMware Tools for WindowsVMware Tools for WindowsVMware Tools for Windows (12.0.0, 11.x.y and 10.x.y)Not stated
VMwareTools10.0.0 through 10.3.24; 11.0.0 through 11.3.5; 12.0.0 up to, but not including, 12.0.512.0.5

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.1HighNVD
CVSS 3.17.1HighCISA (ADP)
CVSS 2.03.6LowNVD

Official description

VMware Tools for Windows(12.0.0, 11.x.y and 10.x.y) contains an XML External Entity (XXE) vulnerability. A malicious actor with non-administrative local user privileges in the Windows guest OS, where VMware Tools is installed, may exploit this issue leading to a denial-of-service condition or unintended information disclosure.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Restriction of XML External Entity Reference

The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output.

How developers prevent this class of flaw

  • Many XML parsers and validators can be configured to disable external entity expansion.

More Improper Restriction of XML External Entity Reference vulnerabilities (CWE-611)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Improper Restriction of XML External Entity Reference vulnerabilities

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