SSRF in Budibase
CVE-2026-54353
Budibase is an open-source low-code platform. Prior to 3.39.9, authenticated users with automation permissions can bypass Budibase's SSRF blacklist through DNS rebinding. The outbound fetch flow validates a hostname against the blacklist before the request is sent, but the actual socket connection later performs a separate DNS lookup through node-fetch. Since the validated IPs are never pinned to the connection, an attacker-controlled hostname can return a public IP during validation and a private/internal IP during the real connection. This results in a non-blind SSRF primitive against internal services reachable from the Budibase host, including loopback, RFC1918 ranges, and cloud metadata endpoints. This vulnerability is fixed in 3.39.9.
Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N.
EPSS exploit prediction
EPSS: 0.002 (10.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 10th percentile — 10.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
- Budibase — versions < 3.39.9
Weakness classification (CWE)
References
- github.com/Budibase/budibase/security/advisories/GHSA-gfq7-5x4g-3xhf (Exploit, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-54353?
- CVE-2026-54353 is a high-severity vulnerability in Budibase, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 8.5/10. Published 2026-06-26.
- How severe is CVE-2026-54353?
- High severity. CVSS v3 base score is 8.5 out of 10.