CVE-2024-7884: When a canister method is called via ic_cdk::call* , a new Future CallFuture is created and can be awaited by the caller to get the execution result....

Description

When a canister method is called via ic_cdk::call* , a new Future CallFuture is created and can be awaited by the caller to get the execution result. Internally, the state of the Future is tracked and stored in a struct called CallFutureState. A bug in the polling implementation of the CallFuture allows multiple references to be held for this internal state and not all references were dropped before the Future is resolved. Since we have unaccounted references held, a copy of the internal state ended up being persisted in the canister's heap and thus causing a memory leak. Impact Canisters built in Rust with ic_cdk and ic_cdk_timers are affected. If these canisters call a canister method, use timers or heartbeat, they will likely leak a small amount of memory on every such operation. In the worst case, this could lead to heap memory exhaustion triggered by an attacker. Motoko based canisters are not affected by the bug. PatchesThe patch has been backported to all minor versions between >= 0.8.0, <= 0.15.0. The patched versions available are 0.8.2, 0.9.3, 0.10.1, 0.11.6, 0.12.2, 0.13.5, 0.14.1, 0.15.1 and their previous versions have been yanked. WorkaroundsThere are no known workarounds at the moment. Developers are recommended to upgrade their canister as soon as possible to the latest available patched version of ic_cdk to avoid running out of Wasm heap memory. Upgrading the canisters (without updating `ic_cdk`) also frees the leaked memory but it's only a temporary solution.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.69%

48.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Dfinity	Canister Developer Kit For The Internet Computer	>= 0.8.0, < 0.8.2
Dfinity	Canister Developer Kit For The Internet Computer	>= 0.9.0, < 0.9.3
Dfinity	Canister Developer Kit For The Internet Computer	>= 0.11.0, < 0.11.6
Dfinity	Canister Developer Kit For The Internet Computer	>= 0.12.0, < 0.12.2
Dfinity	Canister Developer Kit For The Internet Computer	>= 0.13.0, < 0.13.5
Dfinity	Canister Developer Kit For The Internet Computer	0.10.0
Dfinity	Canister Developer Kit For The Internet Computer	0.14.0
Dfinity	Canister Developer Kit For The Internet Computer	0.15.0

References

https://docs.rs/ic-cdk/latest/ic_cdk/Product
https://github.com/dfinity/cdk-rs/pull/509Issue Tracking, Patch
https://internetcomputer.org/docs/current/references/ic-interface-specProduct

Timeline

Published: Sep 5, 2024
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2024-7884?

When a canister method is called via ic_cdk::call* , a new Future CallFuture is created and can be awaited by the caller to get the execution result. Internally, the state of the Future is tracked and stored in a struct called CallFutureState. A bug in the polling implementation of the CallFuture allows multiple references to be held for this internal state and not all references were dropped before the Future is resolved. Since we have unaccounted references held, a copy of the internal state ended up being persisted in the canister's heap and thus causing a memory leak. Impact Canisters built in Rust with ic_cdk and ic_cdk_timers are affected. If these canisters call a canister method, use timers or heartbeat, they will likely leak a small amount of memory on every such operation. In the worst case, this could lead to heap memory exhaustion triggered by an attacker. Motoko based canisters are not affected by the bug. PatchesThe patch has been backported to all minor versions between >= 0.8.0, <= 0.15.0. The patched versions available are 0.8.2, 0.9.3, 0.10.1, 0.11.6, 0.12.2, 0.13.5, 0.14.1, 0.15.1 and their previous versions have been yanked. WorkaroundsThere are no known workarounds at the moment. Developers are recommended to upgrade their canister as soon as possible to the latest available patched version of ic_cdk to avoid running out of Wasm heap memory. Upgrading the canisters (without updating `ic_cdk`) also frees the leaked memory but it's only a temporary solution.

How severe is CVE-2024-7884?

CVE-2024-7884 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.69% probability of exploitation in the next 30 days.

How do I fix CVE-2024-7884?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.