Security readout for executives and security teams
Plain-English summary
Wasm3 0.5.0 contains a memory corruption flaw: an out-of-bounds write during WebAssembly runtime cleanup paths. For executives, the concern is highest where Wasm3 processes untrusted or externally supplied WebAssembly modules. The provided sources do not include CVSS, affected deployment details, or a named fixed version.
Executive priority
Treat this as a targeted inventory and exposure question, not a confirmed emergency. Escalate priority if Wasm3 0.5.0 handles untrusted modules in production or safety-critical systems.
Technical view
CVE-2021-45947 describes an out-of-bounds write in Wasm3 0.5.0 Runtime_Release, reached from EvaluateExpression and InitDataSegments. The record references OSS-Fuzz and Chromium issue tracking. No CWE, CVSS vector, patch version, or exploitability assessment is supplied in the provided bundle.
Likely exposure
Exposure is most likely in applications, services, firmware, or tooling that embed Wasm3 0.5.0 and parse or execute WebAssembly modules, especially from untrusted sources. The bundle does not identify downstream products or CPEs.
Exploitation context
The source bundle does not show active exploitation, and the CVE is not marked in KEV. The referenced origin appears fuzzing-related, but the bundle does not provide enough evidence to assess real-world exploitability or practical attack preconditions.
Researcher notes
Key missing data: CVSS, CWE, fixed version, reproducer details, and affected downstream products. Keep analysis bounded to Wasm3 0.5.0 and the named Runtime_Release path unless additional vendor evidence is obtained.
Mitigation direction
- Inventory applications and components that embed Wasm3 0.5.0.
- Check Wasm3 project guidance for a fixed release or workaround.
- Avoid processing untrusted WebAssembly modules with affected builds.
- Run Wasm workloads in constrained, sandboxed environments where feasible.
- Prioritize updates for internet-facing or user-supplied module paths.
Validation and detection
- Search dependency manifests and vendored code for Wasm3 0.5.0.
- Confirm whether any service accepts external WebAssembly modules.
- Review build artifacts for statically linked or bundled Wasm3 copies.
- Track the OSS-Fuzz and CVE references for fix status.
- After remediation, run regression tests for WebAssembly loading paths.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CVE-2021-45947 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/google/oss-fuzz-vulns/blob/main/vulns/wasm3/OSV-2021-689.yamlCVE reference · x_refsource_MISC
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=33689CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.