Description
The Model Context Protocol has a security warning advising servers to validate the "Origin" header on all incoming connections to prevent DNS rebinding attacks. Prior to the v0.25.0 release, users had no way to validate the origin's host. In v0.25.0, a new "--allowed-hosts" flag was introduced alongside the existing "--allowed-origins" flag, enabling users to specify permitted hosts at server startup. Both flags default to "*", allowing users to implement strict access controls as needed without breaking existing setups. If either flag is set to "*", the server will output a startup warning about potential vulnerabilities. Documentation has also been updated to highlight these security considerations.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| MCP Toolbox for Databases | < 0.25.0 | 0.25.0 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | govulncheck-vulndb | 0.0.20260827T195228-160000.1.1 | SUSE-SU-2026:23625-1 |
| SLES 16.0 | govulncheck-vulndb | 0.0.20260827T195228-160000.1.1 | SUSE-SU-2026:23625-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 16.0 | govulncheck-vulndb | 0.0.20260827T195228-160000.1.1 | openSUSE-SU-2026:21761-1 |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Go | github.com/googleapis/genai-toolbox | < 0.25.0 | 0.25.0 | GO-2026-6288 |
| Go | github.com/googleapis/mcp-toolbox | < 0.25.0 | 0.25.0 | GHSA-76g7-m3xw-x9gr |
Advisories 2
- SUSE-SU-2026:23625-1 Security update for govulncheck-vulndb SUSE / openSUSE Security Updates · Sep 29, 2026
- openSUSE-SU-2026:21761-1 Security update for govulncheck-vulndb SUSE / openSUSE Security Updates · Sep 9, 2026