IBM Langflow Desktop Unauthenticated Image Access via IDOR

IBM Langflow Desktop versions 1.0.0 through 1.8.4 are susceptible to an indirect object reference (IDOR) vulnerability, designated as CVE-2026-4503. This flaw enables unauthenticated attackers to access and view images belonging to other users. The vulnerability arises from the application’s reliance on a user-controlled key to reference objects, which can be manipulated to bypass authorization checks and gain unauthorized access to sensitive image data. This poses a risk to user privacy and data security, as attackers can potentially view confidential or personal images without proper authentication.

Attack Chain

1. An unauthenticated attacker identifies a user-controlled key used to reference image objects within Langflow Desktop.
2. The attacker modifies this key to point to another user’s image object.
3. The attacker sends a request to the Langflow Desktop application using the modified key.
4. The application, due to the IDOR vulnerability, fails to properly validate the attacker’s authorization to access the requested image object.
5. The application retrieves and returns the image data associated with the targeted user’s image.
6. The attacker views the image without authentication.

Impact

Successful exploitation of this vulnerability allows an unauthenticated attacker to view other users’ images within IBM Langflow Desktop. This can lead to a breach of privacy, as sensitive or personal images may be exposed. The number of affected users depends on the number of installations of Langflow Desktop within the vulnerable version range (1.0.0 through 1.8.4).

Recommendation

• Apply the security patch or upgrade to a version of IBM Langflow Desktop that addresses CVE-2026-4503 as detailed in the IBM advisory.
• Implement stricter authorization checks on image object references to prevent unauthorized access, mitigating CVE-2026-4503.