wasmtime has a runtime crash when combining tail calls with trapping imports

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

6.8 · CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N · score source

EPSS

• CVE-2024-47763: 0.24% estimated exploitation activity in the next 30 days; percentile 15.76 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact Wasmtime's implementation of WebAssembly tail calls combined with stack traces can result in a runtime crash in certain WebAssembly modules. The runtime crash may be undefined behavior if Wasmtime was compiled with Rust 1.80 or prior. The runtime crash is a deterministic process abort when Wasmtime is compiled with Rust 1.81 and later. WebAssembly tail calls are a proposal which relatively recently reached stage 4 in the standardization process. Wasmtime first enabled support for tail calls by default in Wasmtime 21.0.0, although that release contained a bug where it was only on-by-default for some configurations. In Wasmtime 22.0.0 tail calls were enabled by default for all configurations. The specific crash happens when an exported function in a WebAssembly module (or component) performs a returncall (or returncallindirect or returncallref) to an imported host function which captures a stack trace (for example, the host function raises a trap). In this situation, the…

Published by the source

9 Oct 2024, 19:14 UTC

Last modified by the source

8 Jun 2026, 20:00 UTC

Source last checked

26 Oct 2026, 15:42 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-q8hx-mm92-4wvg

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# Patch Next advisory brief: CVE-2024-47763

Advisory: wasmtime has a runtime crash when combining tail calls with trapping imports
IDs: CVE-2024-47763, GHSA-q8hx-mm92-4wvg
Record: https://patchnext.com/advisories/cve-2024-47763 (revision 1, source checked 26 Oct 2026, 15:42 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: wasmtime 25.0.2, 24.0.1, 23.0.3, 22.0.1, 21.0.2. A vendor fix does not mean a deployment is fixed.

## Affected components
- crates.io wasmtime: affected >= 12.0.0, < 21.0.2; >= 22.0.0, < 22.0.1; >= 23.0.0, < 23.0.3; >= 24.0.0, < 24.0.1; >= 25.0.0, < 25.0.2; fixed in 24.0.1, 21.0.2, 22.0.1, 25.0.2, 23.0.3

## Suggested inspection (read-only)
- crates.io wasmtime: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on wasmtime.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-q8hx-mm92-4wvg (GitHub-reviewed advisory GHSA-q8hx-mm92-4wvg lists affected ranges: crates.io wasmtime >=12.0.0 =22.0.0 =23.0.0 =24.0.0 =25.0.0 <25.0.2)

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