CVE-2026-56676 Details
Description
9Router is an AI router & token saver. Prior to 0.5.2, 9router validates image URLs by resolving the host before fetching, but open-sse/translator/concerns/image.js performs the later server-side image fetch with a separate DNS resolution. An authenticated attacker with access to the LLM proxy can use a vision-capable model and an attacker-controlled DNS name that first resolves to a public IP and then rebinds to an internal address, allowing server-side requests to internal-only HTTP services. This issue is fixed in version 0.5.2.
A server-side request forgery (SSRF) vulnerability has been identified in 9Router versions prior to 0.5.2. The issue arises from the way the application validates image URLs. Initially, 9Router resolves the host to ensure it points to a public IP before fetching the image. However, the actual fetch operation performs a separate DNS resolution, creating a time-of-check to time-of-use (TOCTOU) vulnerability. An authenticated attacker with access to the LLM proxy can exploit this by using a vision-capable model and an attacker-controlled DNS name that first resolves to a public IP and then rebinds to an internal address. This allows the server-side request to access internal-only HTTP services, such as cloud metadata endpoints or internal admin panels.
Users are advised to update to 9Router version 0.5.2 or later, where this vulnerability has been fixed.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Jul 10, 2026CISA-ADP
Assessed Jul 13, 2026References to Advisories, Solutions, and Tools
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| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/decolua/9router/security/advisories/GHSA-cmhj-wh2f-9cgx | CISA-ADP | AdvisoryExploitRemedyVendor |
| https://github.com/decolua/9router/commit/c7d07448c58bec1200741de0b73305b860416b82 | [email protected] | Source CodeVendor |
| https://github.com/decolua/9router/releases/tag/v0.5.2 | [email protected] | Release NotesVendor |
| https://github.com/decolua/9router/security/advisories/GHSA-cmhj-wh2f-9cgx | [email protected] | AdvisoryExploitRemedyVendor |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-367 | Time-of-check Time-of-use (TOCTOU) Race Condition | [email protected] |
| CWE-918 | Server-Side Request Forgery (SSRF) | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| decolua 9router | <= 0.4.80 (semver) |
CPE
Remediation
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Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jul 13, 2026 | CVE Modified | CISA-ADP |
| Jul 10, 2026 | New CVE Received | [email protected] |