CVE-2026-48150: Budibase: Workspace-scoped builder escalates to global admin via /api/public/v1/roles/assign

Should you act?

Critical, preconditions apply

Severe if exploited, but exploitation needs conditions that may not apply to you. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
• EPSS 0.5%, percentile 40: FIRST’s model estimates a 0.5% chance of exploitation activity in the next 30 days, higher than 40% of all scored CVEs (low). EPSS is a probability, not a verdict.
• Needs an account (high (admin)). Exposure depends on who can log in.
• Only applies if your dependency tree includes @budibase/server (npm) < 3.39.0, fixed in 3.39.0. Check your lockfile, including transitive dependencies.

What it is

Budibase is an open-source low-code platform. Prior to 3.39.0, /api/public/v1/roles/assign is guarded by the builderOrAdmin middleware, which passes any user who is a builder for the app id in the x-budibase-app-id header. That check admits both global builders and workspace-scoped builders (builder.apps set but builder.global unset). The controller then spreads the request body into the SDK call, and the SDK grants builder.global=true or admin.global=true on whichever user ids the caller supplies. Bob, a workspace-scoped builder with an API key, promotes himself or any other user to global admin with one POST. The whole flow is tenant-wide privilege escalation from an app-level role, available to anyone with an Enterprise license that unlocks the EXPANDEDPUBLICAPI feature. This vulnerability is fixed in 3.39.0.

From the GitHub advisory

Summary

/api/public/v1/roles/assign is guarded by the builderOrAdmin middleware, which passes any user who is a builder for the app id in the x-budibase-app-id header. That check admits both global builders and workspace-scoped builders (builder.apps set but builder.global unset). The controller then spreads the request body into the SDK call, and the SDK grants builder.global=true or admin.global=true on whichever user ids the caller supplies. Bob, a workspace-scoped builder with an API key, promotes himself or any other user to global admin with one POST. The whole flow is tenant-wide privilege escalation from an app-level role, available to anyone with an Enterprise license that unlocks the EXPANDEDPUBLICAPI feature.

Details

Controller (packages/server/src/api/controllers/public/roles.ts:13-17):

Nothing filters assignmentProps. The request body's builder and admin keys flow directly into the SDK.

Weakness type: CWE-915.

Product: @budibase/server (npm) · Assigned by: GitHub_M · Published: 2026-05-27

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: high (admin)
• User interaction: none
• Scope: changed (can affect other components)

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation poc, automatable no, technical impact partial.
• FIRST EPSS (model of 2026-10-21): 0.47% probability of exploitation activity in the next 30 days; percentile 40.

Timeline

• 2026-05-27 — CVE record last updated
• 2026-05-27 — CVE record published by GitHub_M
• 2026-06-12 — GitHub-reviewed advisory GHSA-6xp4-cf37-ppjh published (critical)

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-6xp4-cf37-ppjh github.com
2. CVE.org record CVE-2026-48150 cve.org
3. NVD entry CVE-2026-48150 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com

Critical npm advisories · Today’s Security Digest