What’s Vulnerable › Vulnerabilities

CVE-2021-28098

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2021-04-14 · updated 2026-06-17
• Weakness: CWE-59

Description

An issue was discovered in Forescout CounterACT before 8.1.4. A local privilege escalation vulnerability is present in the logging function. SecureConnector runs with administrative privileges and writes logs entries to a file in %PROGRAMDATA%\ForeScout SecureConnector\ that has full permissions for the Everyone group. Using a symbolic link allows an attacker to point the log file to a privileged location such as %WINDIR%\System32. The resulting log file adopts the file permissions of the source of the symbolic link (in this case, the Everyone group). The log file in System32 can be replaced and renamed with a malicious DLL for DLL hijacking.

Affected products

• Forescout Counteract: before 8.1.4 — fixed in 8.1.4

How to fix

Upgrade to a fixed version: Forescout Counteract 8.1.4. Check the vendor advisory for mitigations.

References

• https://docs.forescout.com
• https://jordanpotti.com/2021/03/30/forescout-priv-esc-folder-permissions/
• https://www.adversis.io/research/2021/3/30/forescout-secure-connector-local-privilege-escalation
• https://docs.forescout.com
• https://jordanpotti.com/2021/03/30/forescout-priv-esc-folder-permissions/
• https://www.adversis.io/research/2021/3/30/forescout-secure-connector-local-privilege-escalation

Get alerted when CVE-2021-28098 or the next vulnerability affects your stack