# CVE-2026-73845: CKAN MCP Server: MQA server allowlist bypass via unanchored regex (`isValidMqaServer`)

> An attacker can bypass server allowlist validation to target arbitrary hosts, potentially reading sensitive data or receiving spoofed responses.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 14 Aug 2026
- **Updated:** 14 Aug 2026
- **Also known as:** GHSA-83x6-42hr-jc76

## What is CVE-2026-73845?

CVE-2026-73845 is a medium-severity server-side request forgery vulnerability in ondata ckan-mcp-server, published on 14 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

CKAN MCP Server is a tool for querying CKAN open data portals. Prior to 0.4.112, the ckan_get_mqa_quality and ckan_get_mqa_quality_details tools in src/tools/quality.ts use isValidMqaServer to validate the server_url parameter with a prefix-only regular expression for dati.gov.it, allowing suffix-host and URL-userinfo values to target an attacker-controlled host and return a spoofed response. This issue is fixed in version 0.4.112.

Weakness: CWE-918 (Server-Side Request Forgery), CWE-625 (Permissive Regular Expression), CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2026-73845?

2 open source packages ship an affected version, including @aborruso/ckan-mcp-server.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `@aborruso/ckan-mcp-server` | npm | All versions | 0.4.112 |
| `@aborruso/ckan-mcp-server` | npm | All versions | 0.4.112 |

## How do I fix CVE-2026-73845?

Upgrade @aborruso/ckan-mcp-server to 0.4.112 or later.

## Is CVE-2026-73845 being exploited?

There is no known exploitation of CVE-2026-73845 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-73845 and fix it if it is affected.

What it is: CVE-2026-73845 is a medium-severity server-side request forgery vulnerability in ondata ckan-mcp-server, published on 14 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-73845 in the wild and no public exploit code.

Affected packages and fixed versions:
- @aborruso/ckan-mcp-server (npm): affected all versions; fixed in 0.4.112
- @aborruso/ckan-mcp-server (npm): affected all versions; fixed in 0.4.112

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-73845/ (Markdown: https://insights.sbomify.com/CVE-2026-73845/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-73845
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-73845
- OSV: https://osv.dev/vulnerability/CVE-2026-73845

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-73845/
Summaries are generated and may contain mistakes; the official description above is the record.