CVE-2026-100684
CVE-2026-100684 — Budibase Server 3.41.0 before 3.45.0 Authentication Bypass via OIDC
Budibase versions 3.41.0 before 3.45.0 contain an authentication bypass in the OIDC/SSO login path of @budibase/server. In sso.authenticate, when no existing user matches the incoming SSO subject, the server looks up pending user invites by the IdP-asserted email address alone — without validating an invite code and without an email_verified check (the email_verified gate protects only the existing-account lookup). An attacker who can register at an IdP that the tenant trusts for OIDC and assert a victim's invited email address (even with email_verified=false) claims the pending invite and inherits all of its granted privileges, including builder and admin.global, with no admin exclusion. This results in takeover of the invited principal and, for admin invites, full tenant compromise (access to all apps, datasources including production credentials, and automations); the invite is consumed, denying onboarding to the legitimate invitee.
Published Updated Sources: NVD, budibase (CNA), GitHub
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Exploit code
public exploit, none observed
EPSS
Not scored
FIRST has not published a score
CVSS base
8.1
high · 2 sources
Remediation
The vendor's own words where we have them.
Upgrade server to a fixed release (3.45.0). Apply vendor patches per advisory and restrict external exposure of the affected component until patched.
First 24 hours
Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.
- Identify exposed assets running affected vendor/product/version combinations.
- Prioritize based on EPSS, PoC availability, and external exposure.
- Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.
Affected scope
Vendor, product and version as the advisories word them.
| Vendor | Product | Versions | Status |
|---|---|---|---|
| budibase | server | 3.41.0 to < 3.45.0 | Vulnerable |
| budibase | server | 3.45.0 | Patched |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Availability
High
Confidentiality
High
Integrity
High
Scope
Unchanged
Attack Complexity
High
Attack Vector
Network
Privileges Req
None
User Interaction
None
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 8.1 | CVSS 3.1 | high | 2.2 | 5.9 | NVD, budibase (CNA) |
| 9.2 | CVSS 4.0 | critical | — | — | budibase (CNA) |
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness & attack patterns
- CWE-287Improper Authentication
Inferred from the weakness class — not observed against this CVE.
- T1548Abuse Elevation Control Mechanism
- T1040Network Sniffing
- T1185Browser Session Hijacking
Public exploit
Capability, not use: code existing is a different claim from anyone running it.
Repositories
1
Detection
Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.
- Search application, proxy, and WAF logs for requests touching /SSO, /server.
- Prioritize edge telemetry for network-reachable server.
- Monitor for scanner or exploit-pattern traffic after 1 public PoC repositories were reported.
Timeline
What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.
- 2026
Added · CVSS 3.1 8.1 (AV:N)
Sep 26, 2026 · NVD
Initial · CVE published
Sep 26, 2026 · NVD
References
2 on the record
- github.com/Budibase/budibase/security/advisories/GHSA-35ch-57g2-3g98
Exploit, Third Party Advisory
- www.vulncheck.com/advisories/budibase-server-3.41.0-before-3.45.0-authentication-bypass-via-oidc
Vendor Advisory
Elsewhere on this site
- budibaseevery CVE for this vendor
- Auth Bypasssame class
- CWE-287other pages naming this weakness
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record1
What should defenders know first?
CVE-2026-100684 is Budibase Server 3.41.0 before 3.45.0 Authentication Bypass via OIDC, a high vulnerability affecting server from budibase. The current evidence does not list it in CISA KEV, and the exploit status is: Active exploitation is not confirmed from current sources for CVE-2026-100684. Public exploit evidence is: 1 public PoC repositories reported; 0 marked weaponized in current dataset. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS 8.1 describes technical severity, while EPSS 0% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.