{"id":"CVE-2025-66627","aliases":["GHSA-g4v2-cjqp-rfmq"],"url":"https://o3.security/vulnerability/CVE-2025-66627","summary":"Wasmi's Linear Memory has a Critical Use After Free Vulnerability","details":"### Summary\n\nA use-after-free vulnerability has been discovered in the linear memory implementation of Wasmi. This issue can be triggered by a WebAssembly module under certain memory growth conditions, potentially leading to memory corruption, information disclosure, or code execution.\n\n### Impact\n\n- **Confidentiality:** High – attacker-controlled memory reads possible.\n- **Integrity:** High – memory corruption may allow arbitrary writes.\n- **Availability:** High – interpreter crashes possible.\n\n### Affected Versions\n\nWasmi `v0.41.0` through Wasmi `v1.0.0`.\n\n### Workarounds\n\n- Upgrade to the latest patched version of Wasmi.\n- Consider limiting the maximum linear memory sizes where feasible.\n\n### Credits\n\nThis vulnerability was discovered by **Robert T. Morris (RTM)**.","published":"2025-12-09T02:52:46.938Z","modified":"2026-08-12T03:51:19.542705104Z","cvss":{"score":8.4,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"crates.io","name":"wasmi","fixedVersion":"0.41.2"},{"ecosystem":"crates.io","name":"wasmi","fixedVersion":"0.47.1"},{"ecosystem":"crates.io","name":"wasmi","fixedVersion":"0.51.3"},{"ecosystem":"crates.io","name":"wasmi","fixedVersion":"1.0.1"}],"fix":{"url":"https://github.com/wasmi-labs/wasmi/commit/0e6f0d2a8325602c58d6a53ce1c0e6045eb6a490","label":"wasmi-labs/wasmi@0e6f0d2"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/66xxx/CVE-2025-66627.json"},{"type":"ADVISORY","url":"https://github.com/wasmi-labs/wasmi/security/advisories/GHSA-g4v2-cjqp-rfmq"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-66627"},{"type":"WEB","url":"https://github.com/wasmi-labs/wasmi/commit/0e6f0d2a8325602c58d6a53ce1c0e6045eb6a490"},{"type":"PACKAGE","url":"https://github.com/wasmi-labs/wasmi"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:19.542705104Z"}}