Ecosyste.ms: Advisories
An open API service providing security vulnerability metadata for many open source software ecosystems.
Security Advisories: GSA_kwCzR0hTQS1xODc5LTlnOTUtNTZteM0V3Q
Wrong type for `Linker`-define functions when used across two `Engine`s
Impact
As a Rust library the wasmtime
crate clearly marks which functions are safe and which are unsafe
, guaranteeing that if consumers never use unsafe
then it should not be possible to have memory unsafety issues in their embeddings of Wasmtime. An issue was discovered in the safe API of Linker::func_*
APIs. These APIs were previously not sound when one Engine
was used to create the Linker
and then a different Engine
was used to create a Store
and then the Linker
was used to instantiate a module into that Store
. Cross-Engine
usage of functions is not supported in Wasmtime and this can result in type confusion of function pointers, resulting in being able to safely call a function with the wrong type.
Triggering this bug requires using at least two Engine
values in an embedding and then additionally using two different values with a Linker
(one at the creation time of the Linker
and another when instantiating a module with the Linker
).
It's expected that usage of more-than-one Engine
in an embedding is relatively rare since an Engine
is intended to be a globally shared resource, so the expectation is that the impact of this issue is relatively small.
The fix implemented is to change this behavior to panic!()
in Rust instead of silently allowing it. Using different Engine
instances with a Linker
is a programmer bug that wasmtime
catches at runtime.
Patches
This bug has been patched and users should upgrade to Wasmtime version 0.30.0.
Workarounds
If you cannot upgrade Wasmtime and are using more than one Engine
in your embedding it's recommended to instead use only one Engine
for the entire program if possible. An Engine
is designed to be a globally shared resource that is suitable to have only one for the lifetime of an entire process. If using multiple Engine
s is required then code should be audited to ensure that Linker
is only used with one Engine
.
For more information
If you have any questions or comments about this advisory:
- Reach out to us on the Bytecode Alliance Zulip chat
- Open an issue in the
bytecodealliance/wasmtime
repository
JSON: https://advisories.ecosyste.ms/api/v1/advisories/GSA_kwCzR0hTQS1xODc5LTlnOTUtNTZteM0V3Q
Source: GitHub Advisory Database
Origin: Unspecified
Severity: Moderate
Classification: General
Published: over 2 years ago
Updated: 10 months ago
CVSS Score: 6.3
CVSS vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:H
Identifiers: GHSA-q879-9g95-56mx, CVE-2021-39219
References:
- https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-q879-9g95-56mx
- https://github.com/bytecodealliance/wasmtime/commit/b39f087414f27ae40c44449ed5d1154e03449bff
- https://crates.io/crates/wasmtime
- https://nvd.nist.gov/vuln/detail/CVE-2021-39219
- https://lists.fedoraproject.org/archives/list/[email protected]/message/Z2Z33FTXFQ6EOINVEQIP4DFBG53G5XIY/
- https://lists.fedoraproject.org/archives/list/[email protected]/message/WAVBRYDDUIY2ZR3K3FO4BVYJKIMJ5TP7/
- https://rustsec.org/advisories/RUSTSEC-2021-0110.html
- https://github.com/advisories/GHSA-q879-9g95-56mx
Blast Radius: 21.4
Affected Packages
cargo:wasmtime
Dependent packages: 126Dependent repositories: 2,459
Downloads: 6,801,318 total
Affected Version Ranges: < 0.30.0
Fixed in: 0.30.0
All affected versions: 0.0.0, 0.3.0, 0.7.0, 0.8.0, 0.9.0, 0.10.0, 0.11.0, 0.12.0, 0.13.0, 0.15.0, 0.16.0, 0.17.0, 0.18.0, 0.19.0, 0.20.0, 0.21.0, 0.22.0, 0.23.0, 0.24.0, 0.25.0, 0.26.0, 0.26.1, 0.27.0, 0.28.0, 0.29.0
All unaffected versions: 0.30.0, 0.31.0, 0.32.0, 0.32.1, 0.33.0, 0.33.1, 0.34.0, 0.34.1, 0.34.2, 0.35.0, 0.35.1, 0.35.2, 0.35.3, 0.36.0, 0.37.0, 0.38.0, 0.38.1, 0.38.2, 0.38.3, 0.39.0, 0.39.1, 0.40.0, 0.40.1, 1.0.0, 1.0.1, 1.0.2, 2.0.0, 2.0.1, 2.0.2, 3.0.0, 3.0.1, 4.0.0, 4.0.1, 5.0.0, 5.0.1, 6.0.0, 6.0.1, 6.0.2, 7.0.0, 7.0.1, 8.0.0, 8.0.1, 9.0.0, 9.0.1, 9.0.2, 9.0.3, 9.0.4, 10.0.0, 10.0.1, 10.0.2, 11.0.0, 11.0.1, 11.0.2, 12.0.0, 12.0.1, 12.0.2, 13.0.0, 13.0.1, 14.0.0, 14.0.1, 14.0.2, 14.0.3, 14.0.4, 15.0.0, 15.0.1, 16.0.0, 17.0.0, 17.0.1, 17.0.2, 17.0.3, 18.0.0, 18.0.1, 18.0.2, 18.0.3, 18.0.4, 19.0.0, 19.0.1, 19.0.2