CVE-2026-27572

7.5 HIGH
Published: February 24, 2026 Modified: February 25, 2026
View on NVD

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.

AI Explanation

Get an AI-powered plain-language explanation of this vulnerability and remediation steps.

Login to generate AI explanation

CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://docs.rs/http/1.4.0/http/header/#limitations
Source: security-advisories@github.com
Not Applicable
https://github.com/bytecodealliance/wasmtime/releases/tag/v24.0.6
Source: security-advisories@github.com
Product Release Notes
https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.6
Source: security-advisories@github.com
Product Release Notes
https://github.com/bytecodealliance/wasmtime/releases/tag/v40.0.4
Source: security-advisories@github.com
Product Release Notes
https://github.com/bytecodealliance/wasmtime/releases/tag/v41.0.4
Source: security-advisories@github.com
Product Release Notes
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-243v-98vx-264h
Source: security-advisories@github.com
Third Party Advisory

7 reference(s) from NVD

Quick Stats

CVSS v3 Score
7.5 / 10.0
EPSS (Exploit Probability)
0.1%
22th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

bytecodealliance