Description
Wasmtime 47.0.0 before 48.0.4 and 49.0.0 before 49.0.2 contains a missing GC rooting vulnerability that leaves references live across try_call unrooted when compiling Wasm modules. Attackers can supply Wasm modules whose callee triggers garbage collection, leaving stale or dangling references that cause GC heap corruption or incorrect execution.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| bytecodealliance | wasmtime | 47.0.0 – < 48.0.4, 49.0.0 – < 49.0.2 | 48.0.4 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | rust-wasmtime | No fix yet | — |
| Ubuntu 26.04 LTS | rust-wasmtime | No fix yet | — |
| Ubuntu 24.04 LTS | rust-wasmtime | No fix yet | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | rust | No fix yet | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| crates.io | wasmtime | >= 47.0.0, < 48.0.4 · >= 49.0.0, < 49.0.2 | 48.0.4, 49.0.2 | RUSTSEC-2026-0326 |
References
- GitHub Security Advisory (GHSA-hw8m-q44c-ggrf) vendor-advisory
- VulnCheck Advisory: Wasmtime 47.0.0 before 48.0.4 and 49.0.0 before 49.0.2 GC Heap Corruption via try_call third-party-advisory