Vulnerability · Published Oct 13, 2026 · Assigned by flexera

CVE-2026-4869Potential Privilege Escalation in InstallShield

Medium 5.4

In plain English

A medium-severity security flaw in InstallShield from Flexera. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 1% of all known vulnerabilities).

Severity (CVSS 4.0)5.4Medium

Exploit odds (30 days)0.1%top 98.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

A potential privilege escalation issue was identified in InstallShield version 2025 R2 and earlier when running compressed Basic MSI setup with Prerequisites from an insecure location. If a local administrator launches a compressed Setup.exe with Prerequisites from an unsecured location, the Prerequisite installers also might load from an unsecured location, potentially leading to privilege escalation.

Affected products (as reported)

Vendor	Product	Versions
Flexera	InstallShield	0 – through 2025 R2

Weakness: CWE-426 · Vector: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

References

https://community.revenera.com/s/article/CVE-2026-4869-Potential-Privilege-Escalation-in-InstallShield-2025-R2-running-Setup-Prerequisites-from-an-insecure-directory