Local antivirus termination via symbolic-link file write
Published May 20, 2022 · Updated Aug 3, 2024
Arbitrary file write in Avast Premium Security before 21.11.2500 allows local users to interrupt service through a crafted DLL file. When malware detection is triggered, AvastSvc.exe creates a C-drive directory and database writable by Authenticated Users, enabling a symbolic link to redirect its privileged write. An unprivileged local user must supply the DLL and trigger detection; the redirected write can terminate Avast antivirus and deny service to the affected system.
Summary
What happened
Arbitrary file write in Avast Premium Security before 21.11.2500 allows local users to interrupt service through a crafted DLL file. When malware detection is triggered, AvastSvc.exe creates a C-drive directory and database writable by Authenticated Users, enabling a symbolic link to redirect its privileged write. An unprivileged local user must supply the DLL and trigger detection; the redirected write can terminate Avast antivirus and deny service to the affected system.
The record
- CVE
- CVE-2022-28964
- Published
- May 20, 2022
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-426, T1562.001
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- May 20, 2022CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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