Default installation of `synthetic-monitoring-agent` exposes sensitive information
Date: 2024-09
Affected: go/github.com/grafana/synthetic-monitoring-agent, go/github.com/grafana/synthetic-monitoring-agent/cmd/synthetic-monitoring-agent
Attack vector: other
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2022-46156
CWE: CWE-489
CWE-749
CVSS: 7.2 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N)

### Impact Users running the Synthetic Monitoring agent in their local network are impacted. The authentication token used to communicate with the Synthetic Monitoring API is exposed thru a debugging endpoint. This token can be used to retrieve the Synthetic Monitoring checks created by the user and assigned to the agent identified with that token. The Synthetic Monitoring API will reject connections from already-connected agents, so access to the token does not guarantee access to the checks. ### Patches Fixed version is v0.12.0 Users are advised to rotate the agent tokens. After upgrading to version v0.12.0 or later, it's recommended that user's of distribution packages (e.g. Debian or RedHat and their derivatives) review the configuration stored in `/etc/synthetic-monitoring/synthetic-monitoring-agent.conf`, specifically the `API_TOKEN` variable which has been renamed to `SM_AGENT_API_TOKEN`. ### Workarounds With all previous versions, it's recommended that users review the agent settings and set the HTTP listening address in a manner that limits the exposure, for example, localhost or a non-routed network, by using the command line parameter `-listen-address`, e.g. `-listen-address localhost:4050`. ### References The following changes have been made to address this issue: - [Disable debug endpoint by default](https://github.com/grafana/synthetic-monitoring-agent/pull/373) - [Allow retrieving the token from the environment](https://github.com/grafana/synthetic-mo


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