MISP exposes critical infrastructure settings—specifically the Redis host addresses used by the core application, the ZeroMQ plugin, and the SimpleBackgroundJobs plugin—through its web UI and API to site-admin users. The background job workers trust raw Redis job payloads without additional validation. An attacker who obtains a hijacked site-admin session (for example, through a stored cross-site scripting vulnerability) can modify the Redis host settings to point at an attacker-controlled Redis server and then restart the workers. Once the workers connect to the attackers Redis instance, the attacker can inject malicious job payloads that the workers execute, achieving arbitrary command execution as the worker account. Additionally, the download_attachments_on_load setting, which controls inline attachment rendering, was modifiable through the same interface, allowing a hijacked session to re-enable a feature that could facilitate further client-side attacks. The vulnerability requires site-admin privileges and a prior session-compromise mechanism; it does not require unauthenticated access. The impact is remote code execution in the context of the MISP worker process and potential data exfiltration through the attacker-controlled Redis connection.
The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.
Access control involves the use of several protection mechanisms such as:
When any mechanism is not applied or otherwise fails, attackers can compromise the security of the product by gaining privileges, reading sensitive information, executing commands, evading detection, etc. There are two distinct behaviors that can introduce access control weaknesses: