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CVE-2026-15342 Plane CVE debrief

CVE-2026-15342 is a multi-tenant authorization flaw in Plane's asset-management API. Authenticated users from one workspace can access, delete, or duplicate assets from another workspace by providing the victim workspace slug and asset ID. Affected endpoints return presigned file URLs and enable destructive or duplicative actions without verifying the requester's workspace membership. This flaw allows cross-tenant data exposure, data deletion, and persistent exfiltration of files into an attacker-controlled workspace.

Vendor
Plane
Product
Unknown
CVSS
MEDIUM 6.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-21
Original CVE updated
2026-07-22
Advisory published
2026-07-21
Advisory updated
2026-07-22

Who should care

Users of Plane's asset-management API, especially those with multiple workspaces, should be aware of this vulnerability. Authenticated users with access to one workspace may inadvertently expose or delete assets from another. Security teams and administrators responsible for Plane's deployment and user management should prioritize patching and verify workspace configurations to mitigate unauthorized access.

Technical summary

The vulnerability exists in Plane's asset-management API, where insufficient authorization checks allow authenticated users to perform actions on assets from other workspaces. Specifically, the API endpoints do not verify if the requesting user is a member of the targeted workspace before returning presigned file URLs or executing destructive actions. This oversight enables attackers to access, delete, or duplicate assets across workspaces, leading to potential data breaches and unauthorized data modifications.

Defensive priority

Medium priority due to the CVSS score of 6.5 and the potential for data exposure and deletion.

Recommended defensive actions

  • Apply the vendor's official patch to fix the authorization flaw in the asset-management API.
  • Verify and restrict workspace configurations to ensure proper isolation of assets.
  • Monitor API logs for suspicious cross-tenant access attempts.
  • Implement additional access controls, such as role-based access restrictions.
  • Conduct regular security audits to identify similar vulnerabilities.

Evidence notes

The CVE record and NVD detail provide information about the vulnerability. The source item URL and references offer additional context. Evidence is limited; defenders should verify affected scope and vendor guidance with official advisories, and review compensating controls for exposed systems while remediation is scheduled and verified. Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up. Check relevant monitoring, detection, and logs for exposed assets that need extra review.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-21T17:17:04.450Z and has not been modified since then.