GHSA-243v-98vx-264h

Suggest an improvement
Source
https://github.com/advisories/GHSA-243v-98vx-264h
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/02/GHSA-243v-98vx-264h/GHSA-243v-98vx-264h.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-243v-98vx-264h
Aliases
Related
Published
2026-02-24T21:08:06Z
Modified
2026-02-28T06:25:59.342122Z
Severity
  • 6.9 (Medium) CVSS_V4 - 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 CVSS Calculator
Summary
Wasmtime can panic when adding excessive fields to a `wasi:http/types.fields` instance
Details

Impact

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.

Patches

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.

Workarounds

There are no known workarounds at this time, embedders are encouraged to update to a patched version of Wasmtime.

Resources

Database specific 
{
    "nvd_published_at": "2026-02-24T22:16:32Z",
    "github_reviewed_at": "2026-02-24T21:08:06Z",
    "github_reviewed": true,
    "cwe_ids": [
        "CWE-770"
    ],
    "severity": "MODERATE"
}
References

Affected packages

crates.io / wasmtime

Package

Name
wasmtime
View open source insights on deps.dev
Purl
pkg:cargo/wasmtime

Affected ranges

Type
SEMVER
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
24.0.6

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/02/GHSA-243v-98vx-264h/GHSA-243v-98vx-264h.json"

crates.io / wasmtime

Package

Name
wasmtime
View open source insights on deps.dev
Purl
pkg:cargo/wasmtime

Affected ranges

Type
SEMVER
Events
Introduced
25.0.0
Fixed
36.0.6

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/02/GHSA-243v-98vx-264h/GHSA-243v-98vx-264h.json"

crates.io / wasmtime

Package

Name
wasmtime
View open source insights on deps.dev
Purl
pkg:cargo/wasmtime

Affected ranges

Type
SEMVER
Events
Introduced
37.0.0
Fixed
40.0.4

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/02/GHSA-243v-98vx-264h/GHSA-243v-98vx-264h.json"