CVE-2026-112040: Open Redirect in diem-project diem

An open redirect vulnerability exists in diem-project diem up to commit 116974edfb9a5b8bd69cb13586dc62bcdbb485ad. The issue is located in the Sign-In component within the dmCorePlugin/plugins/dmUserPlugin/modules/dmUser/lib/BasedmUserActions.class.php file. Manipulating the Referer argument enables an attacker to cause an open redirect, potentially redirecting users to malicious sites. The vulnerability can be exploited remotely without privileges and requires user interaction. The project follows a rolling release model, so no fixed or affected versions are specified. The vendor has not yet responded to the issue report.

The vulnerability allows remote attackers to redirect users to arbitrary external URLs via manipulation of the Referer argument. This can facilitate phishing or social engineering attacks by redirecting users to malicious sites. The CVSS 4.0 base score is 5.3 (medium severity), reflecting the need for user interaction and the lack of required privileges. There is no indication of direct code execution or data compromise from this vulnerability alone.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since the vendor has not responded and no patch links are available, users should exercise caution when interacting with links involving the Referer parameter in diem-project diem. Monitoring for updates from the vendor is recommended.