CVE-2026-72859

HIGH CVSS 4.0: 8.3 EPSS 0.18%
Updated Aug 14, 2026
Budibase
Parameter Value
CVSS 8.3 (HIGH)
Affected Versions 3.39.4 — 3.40.0
Fixed In 3.40.0
Type CWE-863 (Incorrect Authorization)
Vendor Budibase
Public PoC No

Budibase versions 3.39.4 before 3.40.0 contain an authorization regression in the S3 attachment upload endpoint that allows BASIC users to obtain S3 PutObject presigned URLs by sending POST requests to the attachments endpoint. The route was changed from a BUILDER permission check to a TABLE/WRITE check, which BASIC users hold by default. Attackers can specify arbitrary S3 buckets in the request body to generate presigned URLs for writing to any bucket accessible by the stored IAM credentials, enabling unauthorized file uploads.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
None
No data leak
Integrity
High
Complete data modification
Availability
None
No disruption

CVSS Vector v4.0

Vulnerable Products 1

Configuration From (including) Up to (excluding)
Budibase Budibase
cpe:2.3:a:budibase:budibase:*:*:*:*:*:*:*:*
3.39.4 3.40.0