CVE-2026-42239
This means every XSS becomes a full account takeover — the attacker steals the JWT and has persistent access to the victim's account.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.28%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 8.1 HIGHCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:N
- EPSS
- 0.28% probability · 21th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-1004
- Affected
- budibase/budibase
- Source
- security-advisories@github.com
References
- https://github.com/Budibase/budibase/releases/tag/3.35.10Patch, Release Notes
- https://github.com/Budibase/budibase/security/advisories/GHSA-4f9j-vr4p-642rExploit, Mitigation, Vendor Advisory
- https://github.com/Budibase/budibase/security/advisories/GHSA-4f9j-vr4p-642rExploit, Mitigation, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.