budibase: Improper Authentication
CVE-2026-73302 is a critical-severity improper authentication vulnerability in budibase, with a CVSS 4.0 base score of 9.0 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected budibase versions: < 3.39.30. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.43% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of budibase you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Attack requirements
- PresentThe target must be in a specific state or configuration for the attack to work.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Confidentiality (vulnerable system)
- HighSerious loss of confidentiality on the vulnerable system.
- Integrity (vulnerable system)
- HighSerious loss of integrity on the vulnerable system.
- Availability (vulnerable system)
- HighSerious loss of availability on the vulnerable system.
- Confidentiality (other systems)
- HighSerious loss of confidentiality on systems beyond the vulnerable one.
- Integrity (other systems)
- HighSerious loss of integrity on systems beyond the vulnerable one.
- Availability (other systems)
- HighSerious loss of availability on systems beyond the vulnerable one.
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA (github.com).
Official description
Budibase is an open-source low-code platform. Prior to 3.39.30, the OIDC flow in packages/backend-core/src/middleware/passport/sso/oidc.ts resolved an email without getEmailVerified or an email_verified requirement, and packages/backend-core/src/middleware/passport/sso/sso.ts then used users.getGlobalUserByEmail as a fallback account-linking key. An attacker who can authenticate through a configured identity provider that asserts a victim email as unverified can have a fresh provider identity merged into the victim Budibase account and inherit the victim roles. This issue is fixed in version 3.39.30.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Authentication
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
How developers prevent this class of flaw
- Use an authentication framework or library such as the OWASP ESAPI Authentication feature.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other vulnerabilities in budibase
- 7.7 High severity
- 8.5 High severity
- 8.4 High severity
- 7.1 High severity
- 7.1 High severity
- 7.6 High severity
Recent Improper Authentication vulnerabilities
- 8.2 High severity
- 7.4 High severity
- 9.8 Critical severity
- 10.0 Critical severity
- 9.8 Critical severity
- 9.1 Critical severity
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