---
id: "CVE-2026-121421"
kind: "vulnerability"
aliases: ["CVE-2026-121421"]
title: "SurrealDB: port-specific network deny rules can be bypassed, enabling internal SSRF"
severity: "medium"
cvss: 5.3
epss: null
exploited: false
status: "open"
category: "ai-tooling"
products: []
ecosystems: []
tags: ["ai-tooling", "database", "self-hosted", "surrealdb"]
not_affected_if: ["no-deny-net-rules", "unauthenticated-only-access"]
published_at: "2026-11-03T15:17:32+00:00"
first_seen_at: "2026-11-03T15:21:59+00:00"
updated_at: "2026-11-03T15:23:31+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-121421", "first_seen_at": "2026-11-03T15:21:59+00:00"}]
---

# SurrealDB: port-specific network deny rules can be bypassed, enabling internal SSRF

SurrealDB 3.1.0 before 3.3.0 has port-specific --deny-net rules that only match literal host strings, and the resolved-IP check ignores the port. An authenticated user calling http::* functions can reach internal services that the deny rules were meant to block.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the SurrealDB version with `surreal version`; affected builds are 3.1.0 up to but not including 3.3.0.
- Check whether the server is started with `--deny-net` rules that use HOST:PORT or IP:PORT forms.

## Fix

- SurrealDB: move to `3.3.0` or later.

## Timeline

- 2026-11-03T15:21:59+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-121421

## Documents

- [advisory] Vendor advisory: github.com https://github.com/surrealdb/surrealdb/security/advisories/GHSA-mhv5-88p6-w4c3
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/surrealdb-3.1.0-before-3.3.0-ssrf-via-port-specific-deny-net-host-aliasing-bypass
- [fix] Patch: github.com https://github.com/surrealdb/surrealdb/commit/9d9a5b0693e499e0d030cac6b618062ec02cd2bc

## From the sources

SurrealDB 3.1.0 before 3.3.0 contains a server-side request forgery vulnerability in network-capability matching because port-specific --deny-net rules (HOST:PORT or IP:PORT) match only a literal host string, while the resolved-IP check discards the port. Authenticated users can call http::* functions with a hostname resolving to a denied IP, or the IP of a denied hostname, to reach blocked internal services.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_