CVE-2026-42239

CWE-1004Published: May 7, 2026· Updated: May 7, 2026

8.1

CVSS v3.1

EPSS:0.03%probability of exploitation in 30 daysPercentile:7.4th

Official 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.

NVD Source

Technical Analysis

CVE-2026-42239 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires high privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), with a CVSS base score of 8.1.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.