Security teams should map who controls the wallet, who can move the asset, and whether the platform or the user holds custody. The key risk is not just theft, but loss of control through compromised keys, weak account security, or unclear responsibility. Governance should treat custody, transfer authority, and recovery as separate controls, especially when assets can move without a central intermediary.
How custody and control shape ownership risk
Shared marketplaces and wallets change the security question from “Is the asset safe?” to “Who can actually exercise control over it?” The practical ownership test is control of the wallet, the signing mechanism, and any recovery path. If those are split across the platform, the end user, or a custodian, teams should treat the asset as a distributed trust relationship rather than a single owned object.
That distinction matters because loss of access can be as damaging as theft. A wallet may be technically intact while the keys, recovery factors, or account session that authorize transfer have already been compromised or weakened.
Where access risk emerges in shared platforms
Access risk is driven by transfer authority, not by visibility alone. A user may see a token, collectible, or balance in an interface while the platform retains operational control, or while a connected account can approve movement without strong friction. In those cases, the main failure mode is unauthorized transfer, accidental transfer, or irreversible loss after account takeover.
Security teams should separate three control questions: who can initiate a move, who can sign or approve it, and who can recover it if the primary path fails. If one party can move assets but another controls recovery, the result is often ambiguous responsibility during incident response.
Assessing custody, transfer authority, and recovery as distinct controls
The cleanest assessment method is to inventory the asset flow end to end. Identify whether the marketplace or wallet operator is a custodian, whether the user holds private keys directly, whether a delegated account can act on behalf of the owner, and whether any transfer can happen without a central intermediary. For wallet-based systems, control is often determined by the strength of authentication, the protection of signing material, and the revocation speed for compromised sessions or credentials.
That is why governance should not merge custody, transfer authority, and recovery into one bucket. Each has a different blast radius: custody answers who holds the asset, transfer authority answers who can move it, and recovery answers who can regain control after compromise or error. Shared marketplaces often fail when these roles are assumed rather than documented.
Risk and Threat Considerations
Shared custody and wallet models create exposure when attackers target the weakest control point, usually the account session, approval workflow, or recovery process. The biggest risk is not only direct theft, but irreversible loss of control when the legitimate owner cannot distinguish platform custody from user authority after compromise.
Failure mechanism: A compromised key, stolen session, weak account recovery path, or overly broad transfer permission lets an attacker move assets before the owner can revoke access or dispute the action.
Impact: The asset can be drained, frozen, or become effectively unrecoverable, and accountability disputes often delay containment because ownership and operational control were never separated cleanly.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
NIST SP 800-53 Rev 5, CIS Controls v8 and OWASP ASVS set the technical controls, while ISO/IEC 27001:2022 and SOC 2 (AICPA) define the regulatory obligations.
| Framework | Control / Reference | Relevance |
|---|---|---|
| NIST SP 800-53 Rev 5 | IA-5 — Authenticator Management | Shared wallets depend on protecting and rotating signing material and recovery factors. |
| AC-6 — Least Privilege | Access risk centers on who can initiate or approve asset movement. | |
| AU-2 — Event Logging | Ownership disputes and unauthorized transfers require traceability across custody actions. | |
| Recommendation — Rotate and protect wallet authenticators and recovery secrets as tightly as other privileged credentials. Limit transfer permissions to the minimum set of accounts and workflows that truly need them. Log transfer, approval, and recovery events so control changes can be reconstructed after incident. | ||
| CIS Controls v8 | CIS-5 — Account Management | Shared wallet risk is driven by account ownership, delegated access, and revocation hygiene. |
| Recommendation — Inventory and promptly disable accounts that can move or recover digital assets. | ||
| ISO/IEC 27001:2022 | A.5.15 — Access control | The question is fundamentally about who is allowed to move assets and under what authority. |
| A.8.5 — Secure authentication | Wallet compromise and unauthorized movement often begin with weak authentication or session control. | |
| Recommendation — Define and enforce access rules that separate custody from transfer authority. Strengthen authentication for wallets and marketplace accounts that can authorize asset movement. | ||
| OWASP ASVS | V8 — Authorization | Asset movement depends on correct authorization checks around transfer and approval actions. |
| V6 — Authentication | Control loss often begins with account takeover or weak recovery authentication. | |
| Recommendation — Verify that transfer and recovery functions enforce explicit authorization at every sensitive step. Require strong authentication on wallet and marketplace accounts that can move assets. | ||
| SOC 2 (AICPA) | CC6.1 — Logical Access Security Software | Shared custody demands controls over logical access to systems that can move assets. |
| Recommendation — Restrict logical access to asset-moving functions and review it regularly. | ||
Practitioner Guidance
What to verify: Confirm which party can initiate transfers, which party can sign them, and which party can revoke or recover access. If the answer changes across asset types or environments, document that difference explicitly and treat it as a higher-risk condition.
Decision rule: If the platform can act without a user-held key, or if the wallet can move assets after a single account compromise, treat the arrangement as high-risk custody and require stronger monitoring, stricter approval boundaries, and faster revocation procedures.
Practitioner takeaway: Ownership risk is controlled by clarity, not labels, so teams should judge shared wallets by actual transfer authority and recovery power, not by whether the interface says the user “owns” the asset.
Related resources from NHI Mgmt Group
- How should security teams evaluate digital ownership models when NFT assets can be bought, sold, and transferred across marketplaces and wallets?
- How should security teams use digital identity wallets without weakening access control?
- How should security teams assess cloud risk when sensitive data and access overlap?
- How should security teams handle identity and access risk in mobile cryptocurrency wallets?
Deepen Your Knowledge
Reviewed and updated by the NHIMG editorial team on September 25, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org
