CVE-2024-27674

SYSTEM code execution via writable service binary

Published Apr 3, 2024 · Updated Oct 28, 2024

Privilege escalation in Grass Software Studio Macro Expert 4.9.4 and earlier allows local users to execute code as SYSTEM. The installation grants BUILTIN\Users modify permission on the program folder, allowing MacroService.exe to be replaced before the service starts. A low-privileged local account must write the replacement binary and wait for a reboot, after which the SYSTEM service executes it.

CVSS severity7.8
High
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Privilege escalation in Grass Software Studio Macro Expert 4.9.4 and earlier allows local users to execute code as SYSTEM. The installation grants BUILTIN\Users modify permission on the program folder, allowing MacroService.exe to be replaced before the service starts. A low-privileged local account must write the replacement binary and wait for a reboot, after which the SYSTEM service executes it.

The record

CVE
CVE-2024-27674
Published
Apr 3, 2024
Updated
Oct 28, 2024
Vendor
Grass Software Studio
Product
Macro Expert
Classifications
CWE-276, T1574.010
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 3, 2024CVE publishedPublication date reported by the CVE source.
  2. Oct 28, 2024Record 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=0 <=4.9.4

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Grass Software Studio · Macro Expertversion=0 <=4.9.4

Published CVSS scores

7.8CISA-ADPCVSS:3.1/AV:L/AC:L/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.

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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-276Incorrect Default Permissions
T1574.010Hijack Execution Flow: Services File Permissions Weakness

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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