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UnratedPublic exploit

Budibase SSRF blacklist bypass via DNS rebinding

IdentifiersCVE-2026-54353CWE-918

CVE-2026-54353 is a server-side request forgery vulnerability in Budibase, an open-source low-code platform, affecting versions prior to 3.39.9. In the outbound fetch flow, Budibase validates the supplied hostname against an SSRF blacklist before sending the request, but the actual network connection is later established by node-fetch, which performs a separate DNS resolution. Because the IP address validated during the initial check is not pinned to the socket connection, an attacker-controlled hostname can resolve to a benign public IP during validation and then re-resolve to a private or internal IP when the real connection is made. This creates a DNS rebinding-based TOCTOU condition that bypasses the blacklist and yields a non-blind SSRF primitive against services reachable from the Budibase host, including loopback, RFC1918 space, and cloud metadata endpoints.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation allows an authenticated user with automation permissions to make Budibase issue attacker-directed requests to internal network targets that should have been blocked by SSRF protections. Reachable targets may include localhost services, RFC1918/internal infrastructure, Kubernetes or VPC-reachable services, and cloud metadata endpoints such as 169.254.169.254. Depending on the environment, this can expose sensitive internal application data, service responses, configuration details, and potentially cloud instance metadata or IAM credentials where metadata hardening is absent. Because the SSRF is described as non-blind, the attacker can obtain response data from the targeted internal services.

Mitigation

If you can’t patch tonight, do this now.

If immediate upgrade is not possible, restrict or closely control which users have automation permissions, as exploitation requires an authenticated user with that capability. Apply egress filtering from the Budibase host to block access to loopback, RFC1918 ranges, link-local addresses, and cloud metadata endpoints where feasible. Monitor outbound connections from the Budibase instance for suspicious requests to internal address space or metadata services. Additional hardening such as metadata service protections and network segmentation can reduce impact, but these are compensating controls rather than a substitute for upgrading.

Remediation

Patch, then assume compromise.

Upgrade Budibase to version 3.39.9 or later. The fix should ensure that outbound fetch validation is bound to the actual destination used for the socket connection, preventing a hostname from being validated against one DNS result and connected using another. In practice, remediation requires eliminating the DNS rebinding gap by validating and enforcing the resolved IP used at connection time rather than relying solely on a pre-request hostname blacklist check.
PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
BudibaseBackend-Coreapplication

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

ACTIVITY FEED

Recent activity

9 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.

9 SOURCESView more in app
What this page doesn’t show

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Exposure mapping

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Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity8

Community discussion across Reddit, Mastodon, and other social sources.

EXTERNAL REFERENCES
MITRE CVE
cve.org · CVE-2026-54353
NVD
nvd.nist.gov/vuln/detail/CVE-2026-54353
MITRE CWE · CWE-918
cwe.mitre.org