Security readout for executives and security teams
Plain-English summary
CVE-2021-45929 describes an out-of-bounds write in Wasm3 0.5.0, a WebAssembly runtime. In plain terms, malformed WebAssembly input could make the software write outside expected memory during compilation logic. The supplied sources do not provide a severity score, patch version, or evidence of active exploitation.
Executive priority
Prioritize discovery over emergency response. This is a memory-safety flaw in a runtime component, but the supplied evidence lacks severity, exploitation, and downstream product detail. Escalate if Wasm3 0.5.0 processes untrusted WebAssembly in exposed or business-critical systems.
Technical view
The issue is reported in Wasm3 0.5.0 in CompileBlock, reachable from CompileElseBlock and Compile_If. The source bundle identifies an out-of-bounds write but provides no CVSS, CWE, downstream affected products, or confirmed fixed version. Treat this as a memory-safety issue requiring dependency validation and vendor guidance.
Likely exposure
Exposure is most likely in software, firmware, or services embedding Wasm3 0.5.0 and processing WebAssembly modules. The supplied evidence does not identify downstream products, deployment patterns, or affected CPEs.
Exploitation context
The CVE is not listed as KEV in the provided bundle. The supplied sources contain no evidence of active exploitation or weaponized exploitation. Risk depends on whether untrusted WebAssembly inputs can reach affected Wasm3 compilation paths.
Researcher notes
Key gaps are missing CVSS, CWE, fixed-version details, and downstream affected products. The most useful research path is confirming reachable Wasm3 0.5.0 usage and whether attacker-controlled WebAssembly can trigger the reported CompileBlock path.
Mitigation direction
- Inventory applications and firmware that embed Wasm3.
- Confirm whether any use Wasm3 0.5.0.
- Check upstream Wasm3 and vendor guidance for fixed versions.
- Restrict untrusted WebAssembly processing until remediation is confirmed.
- Isolate affected parsing or runtime components where practical.
Validation and detection
- Review SBOMs and dependency manifests for Wasm3.
- Check compiled artifacts or vendor attestations for Wasm3 version evidence.
- Identify whether untrusted WebAssembly inputs are accepted.
- Map exposed services to any Wasm3-backed processing path.
- Record remediation status and vendor response for each asset.
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-2021-45929 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-2021-1061.yamlCVE reference · x_refsource_MISC
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=36551CVE 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.