Is This vulnerability exploited in the wild?

No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

How severe is This vulnerability?

Informational severity, published 2 November 2022.

Which products and versions are affected?

apollo-server (npm) SEMVER:introduced=0,fixed=4.1.0; apollo-server-core (npm) SEMVER:introduced=3.0.0,fixed=3.11.0.

Is there a fix for This vulnerability?

Yes. apollo-server (npm): upgrade to 4.1.0 or later; apollo-server-core (npm): upgrade to 3.11.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is This vulnerability attacked?

It is attacked over the network, in a software library.

Check whether you run apollo-server (npm) or apollo-server-core (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Apollo Server incorrect cache-control header in batched requests

Severity: info · Published 2022-11-02

Apollo Server is a GraphQL runtime that processes client requests and sends responses. When clients send multiple GraphQL operations in a single batched HTTP request, the server may return an incorrect cache-control header that reflects the policy of only one operation instead of all operations. This could cause sensitive or session-specific data to be cached and shared inappropriately in CDNs or reverse proxies, potentially exposing one user's data to other users.

Technologies: apollo-server (npm), apollo-server-core (npm). Vendors: npm.

Quick answers

Is This vulnerability exploited in the wild?: No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.
How severe is This vulnerability?: Informational severity, published 2 November 2022.
Which products and versions are affected?: apollo-server (npm) SEMVER:introduced=0,fixed=4.1.0; apollo-server-core (npm) SEMVER:introduced=3.0.0,fixed=3.11.0.
Is there a fix for This vulnerability?: Yes. apollo-server (npm): upgrade to 4.1.0 or later; apollo-server-core (npm): upgrade to 3.11.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is This vulnerability attacked?: It is attacked over the network, in a software library.
Am I affected?: Check whether you run apollo-server (npm) or apollo-server-core (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

apollo-server (npm): upgrade to 4.1.0 or later
```
npm install apollo-server@4.1.0
```
apollo-server-core (npm): upgrade to 3.11.0 or later
```
npm install apollo-server-core@3.11.0
```

Technical details

The vulnerability is an incorrect cache-control header generation (CWE-524) that occurs when Apollo Server processes batched HTTP requests containing multiple GraphQL operations with differing cache policies. In Apollo Server 3 and 4, the response header merging logic arbitrarily selects one operation's cache-control value when multiple operations specify different policies. An attacker can craft a batched POST request combining an operation that should not be cached (containing session-specific data) with an operation that can be cached, resulting in a response header that permits caching the entire response. If the reverse proxy or CDN respects POST request caching, the cached response will include the session-specific data, causing cache poisoning. The vulnerability requires specific server configuration allowing POST caching and does not affect most browser or mobile client caches. Patches are available: Apollo Server 3.11.0+ disables cache-control headers on batched requests entirely; Apollo Server 4.1.0+ implements header merging across all operations.

Affected products

Apollo apollo-server-core 3.0.0 to 3.10.x
Apollo apollo-server 3.0.0 to 3.10.x
Apollo apollo-server-express 3.0.0 to 3.10.x
Apollo @apollo/server before 4.1.0

Timeline

2022-11-02: disclosed: Advisory GHSA-8r69-3cvp-wxc3 published
2022-11-02: patched: Apollo Server 3.11.0 and 4.1.0 released with fixes

References

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