Ivanti Connect Secure Predictable Filename Vulnerability (CVE-2026-118527) - Arbitrary File Upload Risk

The primary remediation is to apply the official security patches provided by Ivanti.

1. Firmware Upgrade - Upgrade to Ivanti Connect Secure 25.1.1.3 or later. - Upgrade to Ivanti Connect Secure 22.8R2.6 or later.

2. Indicator of Compromise (IoC) Scanning - Inspect directories such as `/home/etc/` or web-accessible paths for unauthorized or suspicious files. - Monitor audit logs for unusual file upload activities from authenticated user accounts.

3. Temporary Mitigation - Restrict user permissions to the minimum necessary and ensure the management interface is not exposed to the public internet until the patch is applied.

The vulnerability (CVE-2026-118527) arises from the use of predictable filename generation (CWE-340) within Ivanti Connect Secure (ICS). A remote authenticated attacker can exploit this flaw to upload files with attacker-controlled content to specific, known locations on the disk. While the CVSS score is 4.3 (Medium), its inclusion in the CISA KEV catalog and an EPSS score of 0.94 indicate high exploitation activity in the wild. This vulnerability is typically used as a primitive in a multi-stage attack chain to achieve Remote Code Execution (RCE) or establish persistence by overwriting critical system files or placing web shells.