The SolarWinds Orion API is vulnerable to authentication bypass that could allow a remote attacker to execute API commands.
The SolarWinds Orion Platform is a suite of infrastructure and system monitoring and management products. The SolarWinds Orion API is embedded into the Orion Core and is used to interface with all SolarWinds Orion Platform products.
The SolarWinds Orion API authentication can be bypassed by including specific parameters in the Request.PathInfo portion of a URI request, which could allow an attacker to execute unauthenticated API commands. In particular, if an attacker appends a PathInfo parameter of WebResource.axd, ScriptResource.axd, i18n.ashx, or Skipi18n to a request to a SolarWinds Orion server, SolarWinds may set the SkipAuthorization flag, which may allow the API request to be processed without requiring authentication.
Users should update to the relevant versions of the SolarWinds Orion Platform:
Especially in cases when updates cannot be installed, we recommend that users implement these mitigations to harden the IIS server.