CVE-2023-33156

Local privilege escalation via TOCTOU race

Published Jul 11, 2023 · Updated Feb 28, 2025

A TOCTOU race in Microsoft Malware Protection Engine before 1.1.23050.3 allows local users to elevate privileges. Microsoft has not disclosed the checked resource, intervening state change, or privileged operation that uses the stale result. Exploitation requires low local privileges and winning a high-complexity race, and it can modify protected data or interrupt the service.

CVSS severity7.0
High
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

A TOCTOU race in Microsoft Malware Protection Engine before 1.1.23050.3 allows local users to elevate privileges. Microsoft has not disclosed the checked resource, intervening state change, or privileged operation that uses the stale result. Exploitation requires low local privileges and winning a high-complexity race, and it can modify protected data or interrupt the service.

The record

CVE
CVE-2023-33156
Published
Jul 11, 2023
Updated
Feb 28, 2025
Vendor
Microsoft
Product
Microsoft Malware Protection Engine
Classifications
CWE-367, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 11, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 28, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.1.0.0 <1.1.23050.3

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Microsoft · Microsoft Malware Protection Engineversion=1.1.0.0 <1.1.23050.3

Published CVSS scores

6.3MicrosoftCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H
7.0NVDCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-367Time-of-check Time-of-use (TOCTOU) Race Condition
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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