Description
Wasmtime is a standalone runtime for WebAssembly. There is a bug in Wasmtime's code generator, Cranelift, for AArch64 targets where constant divisors can result in incorrect division results at runtime. This affects Wasmtime prior to version 0.38.2 and Cranelift prior to 0.85.2. This issue only affects the AArch64 platform. Other platforms are not affected. The translation rules for constants did not take into account whether sign or zero-extension should happen which resulted in an incorrect value being placed into a register when a division was encountered. The impact of this bug is that programs executing within the WebAssembly sandbox would not behave according to the WebAssembly specification. This means that it is hypothetically possible for execution within the sandbox to go awry and WebAssembly programs could produce unexpected results. This should not impact hosts executing WebAssembly but does affect the correctness of guest programs. This bug has been patched in Wasmtime version 0.38.2 and cranelift-codegen 0.85.2. There are no known workarounds.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| bytecodealliance | wasmtime | < 0.38.2, < 0.85.2 | — |
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 24.04 LTS | thunderbird | No fix yet | — |
| Ubuntu 22.04 LTS | mozjs78 +2 | No fix yet | — |
| Ubuntu 20.04 LTS | mozjs52 +1 | No fix yet | — |
| Ubuntu 18.04 LTS | mozjs38 +1 | No fix yet | — |