{"id":"CVE-2021-39228","aliases":["GHSA-mc22-5q92-8v85"],"url":"https://o3.security/vulnerability/CVE-2021-39228","summary":"Memory Safety Issue when using patch or merge on state and assign the result back to state","details":"Tremor is an event processing system for unstructured data. A vulnerability exists between versions 0.7.2 and 0.11.6. This vulnerability is a memory safety Issue when using `patch` or `merge` on `state` and assign the result back to `state`. In this case, affected versions of Tremor and the tremor-script crate maintains references to memory that might have been freed already. And these memory regions can be accessed by retrieving the `state`, e.g. send it over TCP or HTTP. This requires the Tremor server (or any other program using tremor-script) to execute a tremor-script script that uses the mentioned language construct. The issue has been patched in version 0.11.6 by removing the optimization and always cloning the target expression of a Merge or Patch. If an upgrade is not possible, a possible workaround is to avoid the optimization by introducing a temporary variable and not immediately reassigning to `state`.","published":"2021-09-17T14:15:08.413Z","modified":"2026-07-09T10:01:21.672493Z","cvss":{"score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":1,"affectedPackages":[{"ecosystem":"crates.io","name":"tremor-script","fixedVersion":"0.11.6"}],"fix":{"url":"https://github.com/tremor-rs/tremor-runtime/commit/1a2efcdbe68e5e7fd0a05836ac32d2cde78a0b2e","label":"tremor-rs/tremor-runtime@1a2efcd"},"references":[{"type":"ADVISORY","url":"https://github.com/tremor-rs/tremor-runtime/releases/tag/v0.11.6"},{"type":"ADVISORY","url":"https://github.com/tremor-rs/tremor-runtime/security/advisories/GHSA-mc22-5q92-8v85"},{"type":"FIX","url":"https://github.com/tremor-rs/tremor-runtime/commit/1a2efcdbe68e5e7fd0a05836ac32d2cde78a0b2e"},{"type":"FIX","url":"https://github.com/tremor-rs/tremor-runtime/pull/1217"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-09T10:01:21.672493Z"}}