Wasmtime can panic when adding excessive fields to a `wasi:http/types.fields` instance (bytecodealliance wasmtime)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.52 % Β· percentile 44 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Analyzed
Description
Wasmtime is a runtime for WebAssembly. Prior to versions 24.0.6, 36.0.6, 4.0.04, 41.0.4, and 42.0.0, Wasmtime's implementation of the `wasi:http/types.fields` resource is susceptible to panics when too many fields are added to the set of headers. Wasmtime's implementation in the `wasmtime-wasi-http` crate is backed by a data structure which panics when it reaches excessive capacity and this condition was not handled gracefully in Wasmtime. Panicking in a WASI implementation is a Denial of Service vector for embedders and is treated as a security vulnerability in Wasmtime. Wasmtime 24.0.6, 36.0.6, 40.0.4, 41.0.4, and 42.0.0 patch this vulnerability and return a trap to the guest instead of panicking. There are no known workarounds at this time. Embedders are encouraged to update to a patched version of Wasmtime.
Weaknesses (CWE)
- CWE-770 β Allocation of Resources Without Limits or Throttling
References
- https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-243v-98vx-264h
- https://github.com/bytecodealliance/wasmtime/commit/301dc7162cca51def19131019af1187f45901c0a
- https://docs.rs/http/1.4.0/http/header/#limitations
- https://github.com/bytecodealliance/wasmtime/releases/tag/v24.0.6
- https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.6
- https://github.com/bytecodealliance/wasmtime/releases/tag/v40.0.4
- https://github.com/bytecodealliance/wasmtime/releases/tag/v41.0.4
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 4.0 | MEDIUM 6.9 | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H | GitHub_M |
| CVSS 4.0 | MEDIUM 6.9 | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X | NVD Β· security-advisories@github.com (Secondary) |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD Β· nvd@nist.gov (Primary) |
European references
- ENISA EUVD Β· EUVD-2026-8569
- GCVE Β· GCVE-0-2026-27572
Affected configurations (NVD CPE)
cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*< 24.0.6cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*β₯ 25.0.0 < 36.0.6cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*β₯ 37.0.0 < 40.0.4cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*β₯ 41.0.0 < 41.0.4
Affected products
| Product | Versions |
|---|---|
| bytecodealliance Β· wasmtime | affected < 24.0.6 ; affected >= 25.0.0, < 36.0.6 ; affected >= 37.0.0, < 40.0.4 ; affected >= 41.0.0, < 41.0.4 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST β attribution requested |
| ENISA EUVD | ENISA β reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain β this product uses data from the NVD API but is not endorsed or certified by the NVD |