SYSTEM code execution via symlink TOCTTOU
Published May 9, 2025 · Updated Oct 13, 2025
Link following in Norton Utilities Ultimate, Avast Cleanup, and AVG TuneUp allows local users to execute arbitrary code as SYSTEM. NortonUtilitiesSvc follows an attacker-created symbolic link across a TOCTTOU window, causing a privileged file operation to act on an attacker-chosen target. A low-privileged account with local execution is required; successful racing elevates code to SYSTEM on affected 64-bit Windows installations.
Summary
What happened
Link following in Norton Utilities Ultimate, Avast Cleanup, and AVG TuneUp allows local users to execute arbitrary code as SYSTEM. NortonUtilitiesSvc follows an attacker-created symbolic link across a TOCTTOU window, causing a privileged file operation to act on an attacker-chosen target. A low-privileged account with local execution is required; successful racing elevates code to SYSTEM on affected 64-bit Windows installations.
The record
- CVE
- CVE-2024-13944
- Published
- May 9, 2025
- Updated
- Oct 13, 2025
- Vendor
- Gen Digital
- Product
- AVG TuneUp
- Classifications
- CWE-59, CWE-367, CAPEC-233, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 9, 2025CVE publishedPublication date reported by the CVE source.
- Oct 13, 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.
- Affected versionversion=0 <=24.3.17165.10564
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
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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