GHSA-2fvv-qxrq-7jq6
apollo-server-core vulnerable to URL-based XSS attack affecting IE11 on default landing page
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
apollo-server-corenpmDescription
Impact
The default landing page contained HTML to display a sample curl command which is made visible if the full landing page bundle could not be fetched from Apollo's CDN. The server's URL is directly interpolated into this command inside the browser from window.location.href. On some older browsers such as IE11, this value is not URI-encoded. On such browsers, opening a malicious URL pointing at an Apollo Router could cause execution of attacker-controlled JavaScript.
This only affects Apollo Server with the default landing page enabled. Old browsers visiting your server may be affected if ANY of these apply:
- You do not pass any landing page plugin to the
pluginsoption ofnew ApolloServer. - You pass
ApolloServerPluginLandingPageLocalDefault()orApolloServerPluginLandingPageProductionDefault()to thepluginsoption ofnew ApolloServer.
Browsers visiting your server are NOT affected if ANY of these apply:
- You pass
ApolloServerPluginLandingPageDisabled()to thepluginsoption ofnew ApolloServer. - You pass
ApolloServerPluginLandingPageGraphQLPlayground()to thepluginsoption ofnew ApolloServer. - You pass a custom plugin implementing the
renderLandingPagehook to thepluginsoption ofnew ApolloServer.
This issue was introduced in v3.0.0 when the landing page feature was added.
Patches
To avoid this, the sample curl command has been removed in release 3.10.1.
Workarounds
Disabling the landing page removes the possibility of exploit:
import { ApolloServerPluginLandingPageDisabled } from 'apollo-server-core';
new ApolloServer({
plugins: [ApolloServerPluginLandingPageDisabled()],
// ...
});
See also
A similar issue exists in the landing page of Apollo Router. See the corresponding Apollo Router security advisory.
For more information
If you have any questions or comments about this advisory:
- Open an issue in the Apollo Server repository
- Email us at [email protected]
Credits
This issue was discovered by Adrian Denkiewicz of Doyensec.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | apollo-server-core | ≥ 3.0.0&&< 3.10.1 | 3.10.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for apollo-server-core. 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 apollo-server-core to 3.10.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-2fvv-qxrq-7jq6 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-2fvv-qxrq-7jq6 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-2fvv-qxrq-7jq6. 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-2fvv-qxrq-7jq6 in your dependencies?
O3 detects GHSA-2fvv-qxrq-7jq6 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.