# CVE-2026-100684: Budibase Server authentication bypass in OIDC/SSO invite reconcile

Source: https://junglewise.ai/threats/cve-2026-100684-budibase-versions-3-41-0-before-3-45-0-contain-an-authentication  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-26. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-100684 · Severity: high · CVSS 8.1 · Published 2026-09-26

Budibase is a low-code application platform that manages user access through identity providers and invite systems. An attacker can claim admin or builder invites intended for another user by authenticating with an OIDC provider and asserting the victim's email address without verification, gaining full access to all apps, databases, and automations or causing the legitimate user to be locked out. This vulnerability allows complete takeover of Budibase tenants when admin invites are compromised.

Technologies: [Budibase Server](https://junglewise.ai/threats/technologies/budibase-server-1). Vendors: [Budibase](https://junglewise.ai/threats/vendors/budibase).

## Quick answers

**Is CVE-2026-100684 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-100684 being exploited in the wild.

**How severe is CVE-2026-100684?** High severity, with a CVSS score of 8.1, published 26 September 2026.

**Which products and versions are affected?** Budibase Server 3.41.0 to 3.44.x.

**Is there a fix for CVE-2026-100684?** A patch was published on 2026-09-26: Fixed in version 3.45.0 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-100684 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-100684?** Check whether you run Budibase Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability exists in the OIDC/SSO authentication path (sso.authenticate) introduced in version 3.41.0. When matching pending user invites to incoming SSO identities, the server looks up invites by email alone without verifying the email_verified flag or requiring an invite code from the attacker. An attacker can register at a trusted IdP with an unverified email matching a pending invite recipient and claim the invite through claimInviteAndSaveUser, which propagates all granted privileges including admin.global with no privilege restrictions, resulting in complete account takeover or tenant compromise.

## Affected products

- Budibase Server 3.41.0 to 3.44.x

## Timeline

- 2026-09-26: disclosed: CVE-2026-100684 published; advisory GHSA-35ch-57g2-3g98 published by Budibase security team
- 2026-09-26: patched: Fixed in version 3.45.0

## References

- [https://github.com/Budibase/budibase/security/advisories/GHSA-35ch-57g2-3g98](https://github.com/Budibase/budibase/security/advisories/GHSA-35ch-57g2-3g98)
- [https://www.vulncheck.com/advisories/budibase-server-3.41.0-before-3.45.0-authentication-bypass-via-oidc](https://www.vulncheck.com/advisories/budibase-server-3.41.0-before-3.45.0-authentication-bypass-via-oidc)

## Related threats

- [Budibase server cross-tenant information disclosure in appPackage endpoint](https://junglewise.ai/threats/cve-2026-100688-budibase-server-before-3-45-0-contains-a-cross-tenant)
- [Budibase Server plaintext credential exposure in external table broadcast](https://junglewise.ai/threats/cve-2026-100687-budibase-server-before-3-45-0-fails-to-redact-plaintext)
- [Budibase Server arbitrary file write via ZIP symlink traversal](https://junglewise.ai/threats/cve-2026-100682-budibase-server-before-3-45-0-contains-an-arbitrary-file-write)