CVE-2026-46424

Budibase: Missing Cache Invalidation on Public API Role Unassignment Allows Revoked Users to Retain Privileges for Up to 1 Hour

export async function unAssign(userIds: string[], opts: AssignmentOpts) {
  // ... modifies user objects: deletes roles, admin, builder ...
  await userDB.bulkUpdate(users)  // line 74
}

export async function bulkUpdateGlobalUsers(users: User[]) {
  const db = getGlobalDB()
  return (await db.bulkDocs(users)) as BulkDocsResponse
}

await cache.user.invalidateUser(response.id)

const EXPIRY_SECONDS = 3600  // 1 hour TTL

user = await getUser({
  userId,
  tenantId: session.tenantId,
  email: session.email,
})

# Prerequisites: Enterprise license, admin API key, a second user with admin role

# Step 1: Confirm user has admin access
curl -s -X GET http://localhost:10000/api/global/roles \
  -H 'Cookie: budibase:auth=<target-user-session>' \
  -H 'x-budibase-app-id: app_xyz'
# Returns 200 with roles list

# Step 2: Revoke admin role via public API
curl -s -X POST http://localhost:10000/api/public/v1/roles/unassign \
  -H 'x-budibase-api-key: <admin-api-key>' \
  -H 'Content-Type: application/json' \
  -d '{"userIds": ["<target-user-id>"], "admin": true}'
# Returns 200, role removed from CouchDB

# Step 3: Verify DB was updated (admin field removed)
# (check CouchDB directly - user document no longer has admin: {global: true})

# Step 4: Immediately retry admin endpoint as revoked user
curl -s -X GET http://localhost:10000/api/global/roles \
  -H 'Cookie: budibase:auth=<target-user-session>' \
  -H 'x-budibase-app-id: app_xyz'
# STILL returns 200, stale cache serves old admin privileges

# Step 5: Wait for cache expiry (up to 3600 seconds) and retry
# After cache expires, the request correctly returns 403

A user whose admin, builder, or app-level roles have been revoked via the public API retains full access to those privileges for up to 1 hour. This is particularly concerning in automated offboarding scenarios where HR/IT systems use the public API to revoke access for terminated employees, the terminated user retains admin/builder access to all applications and data during the cache window.

The impact is bounded by:

• Requires enterprise license (expanded public API feature)
• Maximum 1-hour window before cache expires
• Only affects the public API revocation path; revocations via the admin UI (UserDB.save()) invalidate cache correctly
• The assign direction has the inverse issue (newly granted roles are delayed) but this is less security-critical

The application assigns, modifies, tracks, or checks privileges incorrectly, allowing a user to gain elevated access. Typical impact: privilege escalation beyond the intended level.

CVE-2026-46424 has a CVSS score of 4.2 (Medium). 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 (3.38.2); upgrading removes the vulnerable code path.

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Add cache invalidation to bulkUpdateGlobalUsers or to the callers that need it. The most targeted fix is in the unAssign function:

// packages/pro/src/sdk/publicApi/roles.ts
import { cache } from "@budibase/backend-core"

export async function unAssign(userIds: string[], opts: AssignmentOpts) {
  // ... existing role removal logic ...
  await userDB.bulkUpdate(users)
  
  // Invalidate cache for all affected users
  await Promise.all(
    users.map(user => cache.user.invalidateUser(user._id!))
  )
}

Alternatively, fix it at the bulkUpdate level to prevent future callers from having the same gap:

// packages/backend-core/src/users/db.ts
static async bulkUpdate(users: User[]) {
  const result = await usersCore.bulkUpdateGlobalUsers(users)
  await Promise.all(
    users.map(user => cache.user.invalidateUser(user._id!))
  )
  return result
}

The same fix should also be applied to the assign function in the same file.

1. What is CVE-2026-46424? CVE-2026-46424 is a medium-severity improper privilege management vulnerability in @budibase/backend-core (npm), affecting versions < 3.38.2. It is fixed in 3.38.2. The application assigns, modifies, tracks, or checks privileges incorrectly, allowing a user to gain elevated access.
2. How severe is CVE-2026-46424? CVE-2026-46424 has a CVSS score of 4.2 (Medium). 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 @budibase/backend-core are affected by CVE-2026-46424? @budibase/backend-core (npm) versions < 3.38.2 is affected.
4. Is there a fix for CVE-2026-46424? Yes. CVE-2026-46424 is fixed in 3.38.2. Upgrade to this version or later.
5. Is CVE-2026-46424 exploitable, and should I be worried? Whether CVE-2026-46424 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-2026-46424 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-2026-46424? Upgrade @budibase/backend-core to 3.38.2 or later.

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