Description
Budibase backend-core (@budibase/backend-core, as used by @budibase/server) omits the shared address space range 100.64.0.0/10 from its default SSRF blacklist (DEFAULT_BLACKLIST) used by REST datasource query previews. When the default blacklist is active (i.e., a self-hosted deployment has not defined BLACKLIST_IPS), an authenticated user with the Builder permission can submit a REST datasource query preview request to POST /api/queries/preview targeting a reachable HTTP(S) service in the 100.64.0.0/10 range, causing the server to send a request to that target and return its response through the preview flow. Per the advisory, no released fix was identified at the time of publication; remediation is to add 100.64.0.0/10 to DEFAULT_BLACKLIST.
References2
Metrics
- CVSS 3.1
-
7.1
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N - CVSS 4.0
-
7.1
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/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 - EPSS — exploit probability
- 0% percentile: 23 · as of 8 November 2026
- CWE
- CWE-918
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