Incorrect reliance on Trait memory layout in mopa
Published Dec 26, 2021 · Updated Oct 23, 2026 · Also known as GHSA-2gxj-qrp2-53jv, RUSTSEC-2021-0095, GHSA-8mv5-7x95-7wcf
Original summary
Normalized public record · Updated Oct 23, 2026
Incorrect reliance on Trait memory layout in mopa
Publisher and source text is retained separately from QFinch interpretation.
QFinch assessment
The mopa crate redefines the deprecated TraitObject struct from core::raw. This is done to then transmute a reference to a trait object (&dyn Trait for any trait Trait) into this struct and retrieve the data field for the purpose of downcasting. This is used to implement downcast_ref_unchecked(), in terms of which downcast_ref() is also implemented. Same goes for mutable reference downcasting and Box downcasting.
Evidence: public source recordsAffected products
| Affected package, product or range | Fix status |
|---|---|
| Consult the referenced vendor advisory for affected versions. | Consult source advisory |
Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.
Remediation
Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.
- Confirm the affected product and reachable code path exist in your environment.
- Apply the vendor-supported patch or mitigation from the primary advisory.
- Rescan the exact deployed revision and retain verification evidence.
Evidence coverage
- SSVC priority
- MEDIUM
- Confidence
- 20%
- Aliases
- GHSA-2gxj-qrp2-53jv, RUSTSEC-2021-0095, GHSA-8mv5-7x95-7wcf
Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.
Sources and record history
Record history
Published Dec 26, 2021 · Last refreshed Oct 23, 2026