SYSTEM privilege escalation via forward-slash path traversal
Published Feb 19, 2020 · Updated Aug 12, 2026
Path traversal in Cisco AnyConnect Secure Mobility Client for Windows before 4.8.02042 allows local users to gain SYSTEM privileges. vpndownloader.exe treats only the final backslash as a filename boundary, so a forward slash in a supplied path escapes its temporary installer folder before signature validation. Valid Windows credentials and local access are required; the SYSTEM service can then overwrite arbitrary same-volume files or load a planted DLL.
Summary
What happened
Path traversal in Cisco AnyConnect Secure Mobility Client for Windows before 4.8.02042 allows local users to gain SYSTEM privileges. vpndownloader.exe treats only the final backslash as a filename boundary, so a forward slash in a supplied path escapes its temporary installer folder before signature validation. Valid Windows credentials and local access are required; the SYSTEM service can then overwrite arbitrary same-volume files or load a planted DLL.
The record
- CVE
- CVE-2020-3153
- Published
- Feb 19, 2020
- Updated
- Aug 12, 2026
- Vendor
- ClamAV
- Product
- Cisco Secure Client
- Classifications
- CWE-427, T1574.001
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Feb 19, 2020CVE publishedPublication date reported by the CVE source.
- Oct 1, 2022Exploitation reportedCisco PSIRT attempted exploitation report
- Oct 24, 2022Exploitation reportedCISA Known Exploited Vulnerabilities Catalog entry
- Aug 12, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=unspecified <n/a
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
- Invoke-ExploitAnyConnectPathTraversalproof of concept · demonstrated
- Cisco AnyConnect Privilege Escalations Metasploit modulefunctional · validated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Reported exploitation
- Cisco PSIRT attempted exploitation reportreported exploitation
- CISA Known Exploited Vulnerabilities Catalog entryknown exploited catalog
Technologies
Your stack
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Your stack
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