{"cve":"CVE-2025-64345","nvd":{"published":"2025-11-12T22:15:49.623","modified":"2026-10-18T20:10:00.110","status":"Deferred","description":"Wasmtime is a runtime for WebAssembly. Prior to version 38.0.4, 37.0.3, 36.0.3, and 24.0.5, Wasmtime's Rust embedder API contains an unsound interaction where a WebAssembly shared linear memory could be viewed as a type which provides safe access to the host (Rust) to the contents of the linear memory. This is not sound for shared linear memories, which could be modified in parallel, and this could lead to a data race in the host. Patch releases have been issued for all supported versions of Wasmtime, notably: 24.0.5, 36.0.3, 37.0.3, and 38.0.4. These releases reject creation of shared memories via `Memory::new` and shared memories are now excluded from core dumps. As a workaround, eembeddings affected by this issue should use `SharedMemory::new` instead of `Memory::new` to create shared memories. Affected embeddings should also disable core dumps if they are unable to upgrade. Note that core dumps are disabled by default but the wasm threads proposal (and shared memory) is enabled by default.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:N/I:L/A:N","score":1.8},"cwes":["CWE-362"],"references":["https://docs.rs/wasmtime/latest/wasmtime/struct.Memory.html#method.new","https://docs.rs/wasmtime/latest/wasmtime/struct.SharedMemory.html#method.new","https://docs.wasmtime.dev/stability-release.html","https://github.com/bytecodealliance/wasmtime/commit/9ebb6934f00d58b92fb68ed0e0b16c0ae828ca10","https://github.com/bytecodealliance/wasmtime/releases/tag/v38.0.4"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:16:02.354564667+00:00"},"epss":{"cve":"CVE-2025-64345","score":0.00116,"percentile":0.01615,"date":"2026-10-26"},"kev":null,"osv":[{"id":"GHSA-hc7m-r6v8-hg9q","url":"https://osv.dev/vulnerability/GHSA-hc7m-r6v8-hg9q","summary":"Wasmtime provides unsound API access to a WebAssembly shared linear memory","modified":"2026-09-10T03:50:31.065532842Z","packages":[{"ecosystem":"crates.io","name":"wasmtime","purl":"pkg:cargo/wasmtime","ranges":[">=38.0.0 <38.0.4"],"fixed":["38.0.4"]},{"ecosystem":"crates.io","name":"wasmtime","purl":"pkg:cargo/wasmtime","ranges":[">=37.0.0 <37.0.3"],"fixed":["37.0.3"]},{"ecosystem":"crates.io","name":"wasmtime","purl":"pkg:cargo/wasmtime","ranges":[">=26.0.0 <36.0.3"],"fixed":["36.0.3"]},{"ecosystem":"crates.io","name":"wasmtime","purl":"pkg:cargo/wasmtime","ranges":["<24.0.5"],"fixed":["24.0.5"]}]},{"id":"RUSTSEC-2025-0118","url":"https://osv.dev/vulnerability/RUSTSEC-2025-0118","summary":"Unsound API access to a WebAssembly shared linear memory","modified":"2026-10-12T18:00:07.413203425Z","packages":[{"ecosystem":"crates.io","name":"wasmtime","purl":"pkg:cargo/wasmtime","ranges":[">=0.0.0-0 <24.0.5",">=25.0.0 <36.0.3",">=37.0.0 <37.0.3",">=38.0.0 <38.0.4"],"fixed":["24.0.5","36.0.3","37.0.3","38.0.4"]}]}],"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."]}