Description

A repository publisher without delete permission may modify protected package content under specific conditions.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "6.5",
  "pubDate": "2026-08-12T15:18:22.117Z",
  "pubdate": "2026-08-12T15:18:22.117Z",
  "executiveSummary": "A privilege boundary bypass vulnerability exists within repository package management systems where a repository publisher lacking explicit deletion permissions can nevertheless modify protected package content under specific operational conditions. This security flaw introduces significant risk regarding package integrity, as unauthorized actors with restricted publishing privileges are able to tamper with immutable or protected repository artifacts. The impact includes potential supply chain compromise, unauthorized alteration of software distributions, and the circumvention of intended access control models governing package repositories. The attack capability relies on possessing publisher-level access while lacking delete privileges, exploiting logic flaws in how the repository verifies modification rights against protected states. Exploitation requirements necessitate valid publisher credentials coupled with specific conditions governing package update mechanisms and state validation checks within the target repository architecture.",
  "technicalDetails": "The vulnerability stems from an authorization logic defect in the repository management system's handling of package updates and write operations. Specifically, the root cause lies in the insufficient validation of user permissions when a publisher attempts to overwrite or modify existing package versions that have been designated as protected. While the access control subsystem correctly blocks explicit deletion requests originating from publishers lacking delete permissions, the update or replacement workflow fails to enforce the same stringent checks against mutating protected content.\nThe attack flow proceeds as follows. First, an authenticated attacker with repository publisher privileges identifies a target package or version marked as protected. Second, instead of issuing a delete command—which would be rejected due to lack of privileges—the attacker crafts a specific modification or replacement payload targeting the protected package namespace. Third, the repository backend processes the incoming write request, incorrectly validating the operation as a standard update rather than a destructive modification subject to deletion constraints. Finally, the system accepts the payload, overwriting or altering the protected package content and violating the immutability guarantees of the repository.\nThe vulnerable component resides in the repository server's permission enforcement layer, specifically within the API endpoints handling package publishing, uploading, and version updates. The attack requires network exposure to the repository management interface, valid publisher-level authentication, and an absence of adequate state-checking mechanisms that differentiate between safe additive updates and restricted modifications of protected artifacts. The post-exploitation impact allows malicious actors to inject modified code, alter dependencies, or corrupt software artifacts distributed to consumers, severely undermining repository integrity."
}