{"id":"CVE-2026-27572","revision":"7c108debcd3c4951b3554b494c1568b8","records":[{"revision":"7c108debcd3c4951b3554b494c1568b8","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-27572","aliases":[],"title":"Wasmtime can panic when adding excessive fields to a `wasi:http/types.fields` instance","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.","state":0,"publishedAt":"2026-02-24T21:31:50.186+00:00","modifiedAt":"2026-02-27T20:55:29.879+00:00","affected":[{"ecosystem":"Vendor product","name":"wasmtime","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"bytecodealliance\",\n                    \"product\": \"wasmtime\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 24.0.6\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \">= 25.0.0, < 36.0.6\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \">= 37.0.0, < 40.0.4\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \">= 41.0.0, < 41.0.4\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"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","score":6.9,"severity":"MEDIUM"}],"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"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-27572","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-27572","identifiers":["CVE-2026-27572"]},"retained":false,"historicalAffected":[]}],"coverage":[]}