CVE-2026-108522: Improper Authentication in Studio-Saelix Sencho

The vulnerability in Studio-Saelix Sencho up to version 0.94.1 affects the /api/auth/login endpoint. It occurs because the login limiter relies on the X-Forwarded-For header supplied by the client without verifying if it comes from a trusted proxy. This allows an attacker to rotate the apparent client IP address, circumventing login attempt limits and resulting in improper authentication. The vendor's remediation ignores forwarding headers by default, accepts them only from explicitly configured proxy CIDRs, and implements a separate failed-attempt limit keyed by normalized account identity. The patch identified by commit 79b86ddcd4aefdd6941f098e35990ab397b13c72 addresses this issue.

An attacker can manipulate the X-Forwarded-For header to bypass login attempt limits, potentially enabling unauthorized access by circumventing authentication protections. This improper authentication could lead to unauthorized access to user accounts or sensitive functionality within the affected application.

A patch is available and should be deployed to remediate this vulnerability. The vendor's fix ignores forwarding headers by default, accepts them only from explicitly configured proxy CIDRs, and adds a separate failed-attempt limit keyed by normalized account identity. Applying this patch will prevent exploitation of the improper authentication issue.