GHSA-fjw8-3gp8-4cvx
MEDIUMDenial of service of Minder Server with attacker-controlled REST endpoint
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.
Blast Radius
github.com/stacklok/minderReal-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
The Minder REST ingester is vulnerable to a denial of service attack via an attacker-controlled REST endpoint that can crash the Minder server.
The REST ingester allows users to interact with REST endpoints to fetch data for rule evaluation. When fetching data with the REST ingester, Minder sends a request to an endpoint and will use the data from the body of the response as the data to evaluate against a certain rule. Minder sends the request on these lines: https://github.com/stacklok/minder/blob/daccbc12e364e2d407d56b87a13f7bb24cbdb074/internal/engine/ingester/rest/rest.go#L131-L139
… and parses the response body on these lines:
Minder creates the URL of the endpoint via templating on these lines:
As far as I can tell, at this stage in rule evaluation, users fully control the raw template and the params passed to the template via the RuleType type:
I have not seen anything that enforces users to only send requests to GitHub REST endpoints. If there is such a constraint, it limits the ease with which this vulnerability can be exploited, but it is still possible. If there is not such a constraint, it is easy to exploit this vuln.
When Minder parses the response from a remote endpoint, it reads the response entirely into memory on these lines:
and
If the response is sufficiently large, it can drain memory on the machine and crash the Minder server.
The attacker can control the remote REST endpoints that Minder sends requests to, and they can configure the remote REST endpoints to return responses with large bodies. They would then instruct Minder to send a request to their configured endpoint that would return the large response which would crash the Minder server.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/stacklok/minder | all versions | 0.0.49 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/stacklok/minder. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/stacklok/minder to 0.0.49 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-fjw8-3gp8-4cvx 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 pinpoints whether GHSA-fjw8-3gp8-4cvx is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-fjw8-3gp8-4cvx. 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-fjw8-3gp8-4cvx in your dependencies?
O3 detects GHSA-fjw8-3gp8-4cvx across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.