GHSA-9j4f-f249-q5w8 is a high-severity (CVSS 7.2) CWE-489 vulnerability in github.com/grafana/synthetic-monitoring-agent/cmd/synthetic-monitoring-agent. A fix is available for github.com/grafana/synthetic-monitoring-agent/cmd/synthetic-monitoring-agent — see the affected versions and patch details below.
Default installation of `synthetic-monitoring-agent` exposes sensitive information
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-9j4f-f249-q5w8 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 376,715 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/grafana/synthetic-monitoring-agent/cmd/synthetic-monitoring-agent🐹github.com/grafana/synthetic-monitoring-agentReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
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
- Allow retrieving the token from the environment
- Default to listening on localhost
For more information
If you have any questions or comments about this advisory:
- You can use the Synthetic Monitoring Agent discussions.
- Issues should be reported in the Synthetic Monitoring Agent issues.
- Email us at [email protected].
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/grafana/synthetic-monitoring-agent/cmd/synthetic-monitoring-agent | all versions | 0.12.0go get github.com/grafana/synthetic-monitoring-agent/cmd/synthetic-monitoring-agent@v0.12.0 |
| 🐹Go | github.com/grafana/synthetic-monitoring-agent | all versions | 0.12.0go get github.com/grafana/synthetic-monitoring-agent@v0.12.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/grafana/synthetic-monitoring-agent/cmd/synthetic-monitoring-agent, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/grafana/synthetic-monitoring-agent/cmd/synthetic-monitoring-agent to 0.12.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-9j4f-f249-q5w8 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-9j4f-f249-q5w8 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-9j4f-f249-q5w8. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-9j4f-f249-q5w8 in your dependencies?
O3 Security finds GHSA-9j4f-f249-q5w8 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.