Apollo Router is a configurable, graph router written in Rust to run a federated supergraph that uses Apollo Federation 2. The affected versions of Apollo Router contain a bug that in limited circumstances, could lead to unexpected operations being executed which can result in unintended data or effects. This only affects Router instances configured to use distributed query plan caching. The root cause of this defect is a bug in Apollo Router’s cache retrieval logic: When this defect is present and distributed query planning caching is enabled, asking the Router to execute an operation (whether it is a query, a mutation, or a subscription) may result in an unexpected variation of that operation being executed or the generation of unexpected errors. The issue stems from inadvertently executing a modified version of a previously executed operation, whose query plan is stored in the underlying cache (specifically, Redis). Depending on the type of the operation, the result may vary. For a query, results may be fetched that don’t match what was requested (e.g., rather than running `fetchUsers(type: ENTERPRISE)` the Router may run `fetchUsers(type: TRIAL)`. For a mutation, this may result in incorrect mutations being sent to underlying subgraph servers (e.g., rather than sending `deleteUser(id: 10)` to a subgraph, the Router may run `deleteUser(id: 12)`. Users who are using distributed query plan caching, are advised to either upgrade to version 1.45.1 or above or downgrade to version 1.43.2 of the Apollo Router. Apollo Router versions 1.44.0 or 1.45.0 are not recommended for use and have been withdrawn. Users unable to upgrade can disable distributed query plan caching to mitigate this issue.
The bug lies in the logic of retrieving data from the Apollo Router cache. When distributed query plan caching is active, the Router may retrieve a query plan from the cache (Redis) from a previously executed operation and use it to process the current request — even if the operations differ in parameters. As a result, instead of executing the requested operation (e.g., `fetchUsers(type: ENTERPRISE)`), the Router may execute its modified version with different arguments (e.g., `fetchUsers(type: TRIAL)`). Similarly, for mutations — the Router may send a command to the subgraph operating on a completely different object than intended (e.g., `deleteUser(id: 12)` instead of `deleteUser(id: 10)`).
An attacker or even a regular user can inadvertently cause disclosure of data not matching their request or trigger unintended data modifications (incorrect mutations) on subgraph servers, leading to violations of data confidentiality, integrity, and availability.
Apollo Router should be updated to version 1.45.1 or later. Alternatively, you can downgrade to version 1.43.2. Versions 1.44.0 and 1.45.0 are not recommended for use and have been withdrawn. If an update is not possible immediately, the distributed query plan caching feature should be disabled as a measure to mitigate the vulnerability.
Apollo Router in versions 1.44.0 and 1.45.0, only when distributed query plan caching (based on Redis) is enabled. These versions have been withdrawn by the manufacturer.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H