CVE-2023-20178Public exploit

SYSTEM escalation via insecure update-directory permissions

Published Jun 28, 2023 · Updated Aug 2, 2024

Local privilege escalation in Cisco Secure Client 5.0 and AnyConnect 4.10 and earlier allows local users to execute code as SYSTEM. The SYSTEM-level vpndownloader.exe process assigns weak permissions to a temporary update directory, allowing its Windows Installer rollback files to be replaced. Exploitation requires low-privileged local access and a successful VPN connection that starts the client update process; the resulting rollback executes attacker-controlled code as SYSTEM.

CVSS severity7.8
High
EPSS probability5.37%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Local privilege escalation in Cisco Secure Client 5.0 and AnyConnect 4.10 and earlier allows local users to execute code as SYSTEM. The SYSTEM-level vpndownloader.exe process assigns weak permissions to a temporary update directory, allowing its Windows Installer rollback files to be replaced. Exploitation requires low-privileged local access and a successful VPN connection that starts the client update process; the resulting rollback executes attacker-controlled code as SYSTEM.

The record

CVE
CVE-2023-20178
Published
Jun 28, 2023
Updated
Aug 2, 2024
Vendor
ClamAV
Product
Cisco Secure Client
Classifications
CWE-276, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 28, 2023CVE publishedPublication date reported by the CVE source.
  2. Aug 2, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=4.10.00093
  2. Affected versionversion=4.10.01075
  3. Affected versionversion=4.10.02086
  4. Affected versionversion=4.10.03104
  5. Affected versionversion=4.10.04065
  6. Affected versionversion=4.10.04071
  7. Affected versionversion=4.10.05085
  8. Affected versionversion=4.10.05095
  9. Affected versionversion=4.10.05111
  10. Affected versionversion=4.10.06079
  11. Affected versionversion=4.10.06090
  12. Affected versionversion=4.9.00086
  13. Affected versionversion=4.9.01095
  14. Affected versionversion=4.9.02028
  15. Affected versionversion=4.9.03047
  16. Affected versionversion=4.9.03049
  17. Affected versionversion=4.9.04043
  18. Affected versionversion=4.9.04053
  19. Affected versionversion=4.9.05042
  20. Affected versionversion=4.9.06037
  21. Affected versionversion=5.0.00238
  22. Affected versionversion=5.0.00529
  23. Affected versionversion=5.0.00556
  24. Affected versionversion=5.0.01242

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

ClamAV · Cisco Secure Clientversion=4.10.00093; version=4.10.01075; version=4.10.02086; version=4.10.03104; version=4.10.04065; version=4.10.04071; version=4.10.05085; version=4.10.05095; version=4.10.05111; version=4.10.06079; version=4.10.06090; version=4.9.00086; version=4.9.01095; version=4.9.02028; version=4.9.03047; version=4.9.03049; version=4.9.04043; version=4.9.04053; version=4.9.05042; version=4.9.06037; version=5.0.00238; version=5.0.00529; version=5.0.00556; version=5.0.01242

Published CVSS scores

7.8CiscoCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:X/RL:X/RC:X

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-276Incorrect Default Permissions
T1068Exploitation for Privilege Escalation

Public exploit references

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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