What’s Vulnerable › Vulnerabilities

CVE-2026-42239: Budibase auth session cookies are set with httpOnly:false — any XSS can lead to full account takeover

• Severity: high (CVSS 8.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-05-07 · updated 2026-06-17
• Weakness: CWE-1004

Description

Budibase is an open-source low-code platform. Prior to version 3.35.10, the budibase:auth cookie containing the JWT session token is set with httpOnly: false at packages/backend-core/src/utils/utils.ts:218. JavaScript can read this cookie via document.cookie. This means every XSS becomes a full account takeover — the attacker steals the JWT and has persistent access to the victim's account. The cookie also lacks secure: true (sent over plaintext HTTP) and sameSite attribute. This issue has been patched in version 3.35.10.

Affected products

• budibase: before 3.35.10 — fixed in 3.35.10

How to fix

Upgrade to a fixed version: budibase 3.35.10. Check the vendor advisory for mitigations.

References

• https://github.com/Budibase/budibase/releases/tag/3.35.10
• https://github.com/Budibase/budibase/security/advisories/GHSA-4f9j-vr4p-642r
• https://github.com/Budibase/budibase/security/advisories/GHSA-4f9j-vr4p-642r

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