{"cve":"CVE-2026-27204","nvd":{"published":"2026-02-24T22:16:32.480","modified":"2026-06-17T10:26:50.570","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 WASI host interfaces are susceptible to guest-controlled resource exhaustion on the host. Wasmtime did not appropriately place limits on resource allocations requested by the guests. This serves as a Denial of Service vector. Wasmtime 24.0.6, 36.0.6, 40.0.4, 41.0.4, and 42.0.0 have all been released with the fix for this issue. These versions do not prevent this issue in their default configuration to avoid breaking preexisting behaviors. All versions of Wasmtime have appropriate knobs to prevent this behavior, and Wasmtime 42.0.0-and-later will have these knobs tuned by default to prevent this issue from happening. There are no known workarounds for this issue without upgrading. Embedders are recommended to upgrade and configure their embeddings as necessary to prevent possibly-malicious guests from triggering this issue.","cvss_v4":{"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},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":6.5},"cwes":["CWE-770","CWE-400","CWE-774","CWE-789"],"references":["https://docs.rs/wasmtime-wasi/latest/wasmtime_wasi/struct.WasiCtxBuilder.html#method.max_random_size","https://docs.rs/wasmtime/latest/wasmtime/component/struct.ResourceTable.html#method.set_max_capacity","https://docs.rs/wasmtime/latest/wasmtime/struct.Store.html#method.set_hostcall_fuel","https://docs.wasmtime.dev/security-what-is-considered-a-security-vulnerability.html","https://github.com/bytecodealliance/wasmtime/issues/11552"],"products":["bytecodealliance:wasmtime"],"source":"nvd","synced_at":"2026-10-19T22:24:17.937441719+00:00"},"epss":{"cve":"CVE-2026-27204","score":0.00404,"percentile":0.34632,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-852m-cvvp-9p4w","url":"https://osv.dev/vulnerability/GHSA-852m-cvvp-9p4w","summary":"Wasmtime WASI implementations are vulnerable to guest-controlled resource exhaustion","modified":"2026-09-10T03:50:34.409495188Z","packages":[{"ecosystem":"crates.io","name":"wasmtime","purl":"pkg:cargo/wasmtime","ranges":["<24.0.6"],"fixed":["24.0.6"]},{"ecosystem":"crates.io","name":"wasmtime","purl":"pkg:cargo/wasmtime","ranges":[">=25.0.0 <36.0.6"],"fixed":["36.0.6"]},{"ecosystem":"crates.io","name":"wasmtime","purl":"pkg:cargo/wasmtime","ranges":[">=37.0.0 <40.0.4"],"fixed":["40.0.4"]}]},{"id":"RUSTSEC-2026-0020","url":"https://osv.dev/vulnerability/RUSTSEC-2026-0020","summary":"Guest-controlled resource exhaustion in WASI implementations","modified":"2026-10-12T18:00:08.826399541Z","packages":[{"ecosystem":"crates.io","name":"wasmtime","purl":"pkg:cargo/wasmtime","ranges":[">=0.0.0-0 <24.0.6",">=25.0.0 <36.0.6",">=37.0.0 <40.0.4",">=41.0.0 <41.0.4"],"fixed":["24.0.6","36.0.6","40.0.4","41.0.4"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}