Because the token becomes a propagation mechanism, not just an authentication secret. If an attacker steals npm, PyPI, or Cargo access, they can extend the compromise into package publication, self-duplication, and downstream distribution, which multiplies blast radius across ecosystems.
Why reuse turns a publishing token into a propagation mechanism
A registry or publishing token stops being a simple login secret once the same value can authenticate across multiple developer systems. At that point, one compromise can authorize package publication, CI/CD access, repo actions, and automation runs that were meant to be separate. The security problem is not only theft, but the trust expansion that reuse creates.
When developers reuse the same token in npm, PyPI, Cargo, container registries, and build tooling, compromise in one place becomes usable in many others. That shared credential turns an isolated incident into a cross-ecosystem control failure because the attacker can move from initial access to publication, modification, and distribution without needing a new foothold for each platform.
Registry token reuse is especially dangerous because publication privileges are inherently high impact. A token that can upload a package can also replace trusted code with malicious code, republish under a maintainer’s name, or trigger downstream consumers to ingest the poisoned artifact automatically. The result is a supply chain path that scales with trust, not just with the size of the original compromise.
How the blast radius grows across developer ecosystems
Developer ecosystems are interconnected by package managers, build pipelines, signing steps, mirrors, and automation hooks. If a single token is accepted in more than one of those paths, an attacker can use it to establish persistence through repeated publication or to seed malicious updates into multiple registries. That is why token reuse is more dangerous than one-off secret exposure in a single service.
One compromised publishing secret can also become a self-replication mechanism. After the attacker gains one registry path, they can push a malicious package that steals more credentials from developers or CI jobs, then use those newly captured tokens to publish again. In other words, the token can help bootstrap a worm-like chain rather than just a one-time intrusion.
This is why registry compromise often looks like a software supply chain issue even when the initial failure is credential hygiene. The attack path is built from authentication, authorization, and distribution trust all being tied to the same reusable secret. Nx s1ngularity attack 2025 and GlassWorm campaign 2025 both illustrate how stolen publishing tokens can be reused to spread further.
What controls reduce the risk of reused publishing tokens
The strongest control is to stop treating publishing tokens as broadly reusable credentials. Separate tokens by ecosystem, by environment, and by purpose so that compromise in one place does not automatically grant publication rights elsewhere. Where possible, prefer short-lived, audience-bound credentials or keyless publishing flows over long-lived shared secrets.
Build and release systems should also assume that any token reaching a developer workstation, CI log, extension, or browser session may eventually be copied or replayed. That means token scope, expiry, rotation, and revocation matter as much as initial issuance. CI/CD Pipeline Identity Security Guide is useful when you are mapping those controls to publishing workflows, and Guide to the Secret Sprawl Challenge is useful when the problem is broader secret spread across developer systems.
Hardening the publication path also means reducing the chance that a stolen token can be replayed from anywhere. Sender-constrained or proof-of-possession approaches, tighter trust boundaries, and provenance checks make token theft less valuable because the secret alone is no longer enough to publish. The practical goal is to make publishing authority narrow, traceable, and hard to transfer.
Risk and Threat Considerations
Reuse creates correlated failure: one stolen publishing secret can unlock multiple registries, multiple teams, and multiple downstream consumers at once. That correlation is what turns a routine credential leak into a supply chain event, because the attacker is not just logging in, they are inheriting the ability to distribute code at scale.
Failure mechanism: The same token is accepted across tools, registries, or automation paths, so a single leak enables package upload, version replacement, or malicious republishing in more than one ecosystem.
Impact: An attacker can spread malicious packages, harvest additional secrets from build or developer systems, and increase blast radius from one account to many dependent projects.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
OWASP Non-Human Identity Top 10, OWASP API Security Top 10 and MITRE ATT&CK address the attack and risk surface, while NIST SP 800-53 Rev 5 and SLSA set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-02 — Secret Leakage | Reusable publishing tokens create supply-chain exposure when leaked or copied. |
| NHI-05 — Overprivileged NHI | Cross-ecosystem reuse often gives one token more publishing power than needed. | |
| NHI-09 — NHI Reuse | The question is directly about the risk created when the same token is reused across ecosystems. | |
| Recommendation — Scope and rotate publishing secrets so one leak cannot authenticate across multiple ecosystems. Reduce token scope so each registry credential can only perform one narrowly defined publishing task. Eliminate credential reuse across registries, CI systems, and release paths. | ||
| NIST SP 800-53 Rev 5 | IA-5 — Authenticator Management | Publishing tokens need lifecycle controls for issuance, storage, rotation, and revocation. |
| AC-6 — Least Privilege | The risk is amplified when one token can publish beyond its intended scope. | |
| SA-12 — Supply Chain Protection | Registry token reuse directly affects software supply chain integrity and distribution trust. | |
| Recommendation — Manage token lifecycle so publication secrets are short-lived, scoped, and revocable. Limit each publishing credential to the minimum registry and action set required. Protect package publication paths with provenance, verification, and constrained release authority. | ||
| OWASP API Security Top 10 | API2 — Broken Authentication | A reusable token across ecosystems creates a broken trust boundary if stolen or replayed. |
| API5 — Broken Function Level Authorization | Publishing authority can cross intended boundaries when one token can perform multiple release functions. | |
| Recommendation — Bind authentication to the intended system so a stolen token cannot be replayed elsewhere. Separate publish permissions so one credential cannot perform unrelated release actions. | ||
| SLSA | Build provenance and integrity | Registry token abuse undermines artifact integrity and trusted release provenance. |
| Recommendation — Require verifiable provenance and trusted publishing paths for released packages. | ||
| MITRE ATT&CK | T1552 — Unsecured Credentials | Attackers commonly steal publishing tokens from developer systems, logs, and build paths. |
| Recommendation — Hunt for credential exposure in developer tooling, CI logs, and package workflows. | ||
Practitioner Guidance
What to prioritise: Inventory every token that can publish or modify packages, then separate by ecosystem and privilege level. If one token can publish to more than one registry or environment, treat that as an immediate blast-radius problem rather than a convenience feature.
What to verify: Confirm whether publishing authority is still long-lived, manually issued, or shared between developers and CI. The control is only working if a stolen token from one workflow cannot publish in another workflow without an explicit additional trust step.
Common mistake: Teams rotate tokens but keep the same cross-ecosystem design. Rotation helps only if reuse and overbroad scope are removed at the same time.
Practitioner takeaway: The key question is not whether a publishing token authenticates successfully, but whether that authentication can be replayed into a broader distribution path than the original owner intended.
Related resources from NHI Mgmt Group
- Why do exposed model registry tokens create supply-chain risk?
- Why do bearer tokens create risk in MCP if they are reused across systems?
- Why do stolen publishing tokens create such a large supply chain risk?
- Why do compromised CI and developer credentials create such a large supply chain risk for Python ecosystems?