CVE-2026-9661

HIGH
Published Nov 13, 2026 CWE-427

Description

Poste Italiane Postecert FIRMAOK! 1.6.29 on Windows contains a local privilege escalation vulnerability caused by an uncontrolled OpenSSL search path, where launcher.exe and dependent executables such as updater.exe and tslupdater.exe load OpenSSL configuration and library files from a hardcoded, user-writable directory that does not exist by default. A low-privileged local attacker can create this missing directory and place malicious OpenSSL configuration or library files inside it, causing the application to load and execute attacker-controlled code with the privileges of the user running it, enabling horizontal or, when a higher-privileged user runs the application, vertical privilege escalation up to full system compromise.

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CVSS v3.1 Score

7.0
HIGH
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-427 CWE-427

References

Frequently Asked Questions

What is CVE-2026-9661? +
Poste Italiane Postecert FIRMAOK! 1.6.29 on Windows contains a local privilege escalation vulnerability caused by an uncontrolled OpenSSL search path, where launcher.exe and dependent executables such as updater.exe and tslupdater.exe load OpenSSL configuration and library files from a hardcoded, user-writable directory that does not exist by default. A low-privileged local attacker can create this missing directory and place malicious OpenSSL configuration or library files inside it, causing the application to load and execute attacker-controlled code with the privileges of the user running it, enabling horizontal or, when a higher-privileged user runs the application, vertical privilege escalation up to full system compromise. It has a CVSS v3.1 base score of 7.0 (HIGH).
How severe is CVE-2026-9661? +
CVE-2026-9661 has a CVSS v3.1 score of 7.0 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.
How do I check if I'm vulnerable to CVE-2026-9661? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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