# CVE-2024-7884: Memory leak when calling a canister method via `ic_cdk::call` > An attacker can trigger heap memory exhaustion in Rust canisters by exploiting a memory leak in the ic_cdk library, causing denial of service. - **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 5 Sep 2024 - **Updated:** 5 Sep 2024 - **Also known as:** GHSA-rwq6-crjg-9cpw, RUSTSEC-2024-0372 ## What is CVE-2024-7884? CVE-2024-7884 is a high-severity denial of service vulnerability in Internet Computer ic-cdk, published on 5 Sep 2024. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official 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. Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime) ## Which versions are affected by CVE-2024-7884? 17 open source packages ship an affected version, including ic_cdk and ic-cdk. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `ic_cdk` | crates.io | From 0.10.0 | 0.10.1 | | `ic_cdk` | crates.io | From 0.10.0 | 0.10.1 | | `ic_cdk` | crates.io | From 0.11.0 | 0.11.6 | | `ic_cdk` | crates.io | From 0.11.0 | 0.11.6 | | `ic_cdk` | crates.io | From 0.12.0 | 0.12.2 | | `ic_cdk` | crates.io | From 0.12.0 | 0.12.2 | | `ic_cdk` | crates.io | From 0.13.0 | 0.13.5 | | `ic_cdk` | crates.io | From 0.13.0 | 0.13.5 | | `ic_cdk` | crates.io | From 0.14.0 | 0.14.1 | | `ic_cdk` | crates.io | From 0.14.0 | 0.14.1 | | `ic_cdk` | crates.io | From 0.15.0 | 0.15.1 | | `ic_cdk` | crates.io | From 0.15.0 | 0.15.1 | | `ic_cdk` | crates.io | From 0.8.0 | 0.8.2 | | `ic_cdk` | crates.io | From 0.8.0 | 0.8.2 | | `ic_cdk` | crates.io | From 0.9.0 | 0.9.3 | | `ic_cdk` | crates.io | From 0.9.0 | 0.9.3 | | `ic-cdk` | crates.io | From 0.8.0 | 0.8.2, 0.9.3, 0.10.1, 0.11.6, 0.12.2, 0.13.5, 0.14.1, 0.15.1, 0.16.0 | Products: Dfinity Canister Developer Kit for the Internet Computer. ## How do I fix CVE-2024-7884? Upgrade ic_cdk to a fixed version for your release line: 0.10.1, 0.11.6, 0.12.2 or 0.13.5. ## Is CVE-2024-7884 being exploited? There is no known exploitation of CVE-2024-7884 in the wild and no public exploit code. ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2024-7884 and fix it if it is affected. What it is: CVE-2024-7884 is a high-severity denial of service vulnerability in Internet Computer ic-cdk, published on 5 Sep 2024. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: There is no known exploitation of CVE-2024-7884 in the wild and no public exploit code. Affected packages and fixed versions: - ic_cdk (crates.io): affected from 0.10.0; fixed in 0.10.1 - ic_cdk (crates.io): affected from 0.10.0; fixed in 0.10.1 - ic_cdk (crates.io): affected from 0.11.0; fixed in 0.11.6 - ic_cdk (crates.io): affected from 0.11.0; fixed in 0.11.6 - ic_cdk (crates.io): affected from 0.12.0; fixed in 0.12.2 - ic_cdk (crates.io): affected from 0.12.0; fixed in 0.12.2 - ic_cdk (crates.io): affected from 0.13.0; fixed in 0.13.5 - ic_cdk (crates.io): affected from 0.13.0; fixed in 0.13.5 - ic_cdk (crates.io): affected from 0.14.0; fixed in 0.14.1 - ic_cdk (crates.io): affected from 0.14.0; fixed in 0.14.1 - ic_cdk (crates.io): affected from 0.15.0; fixed in 0.15.1 - ic_cdk (crates.io): affected from 0.15.0; fixed in 0.15.1 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2024-7884/ (Markdown: https://insights.sbomify.com/CVE-2024-7884/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2024-7884 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-7884 - OSV: https://osv.dev/vulnerability/CVE-2024-7884 --- From sbomify Insights: https://insights.sbomify.com/CVE-2024-7884/ Summaries are generated and may contain mistakes; the official description above is the record.