External risk intelligence

Verba RAG SSRF and Middleware Bypass Vulnerability.

CVE advisorySeverity: CRITICAL (CVSS 9.2)

CVE-2026-65317

Verba is a RAG (Retrieval-Augmented Generation) application. Such applications are commonly deployed as web-facing services or APIs to allow users or integrated systems to query data, making their API endpoints, including those handling connection requests, reachable via the internet in standard deployments.

Server-Side Request Forgery

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A critical vulnerability has been identified in Verba RAG applications that could allow unauthenticated attackers to force the server to issue arbitrary HTTP requests. This occurs by exploiting a combination of server-side request forgery and a middleware bypass, enabling attackers to potentially interact with internal or external systems through the compromised application. The main concern is confirming relevance and exposure to understand potential impacts.

Attackers can trick the application into making requests.
This vulnerability could expose internal or external systems.
Confirm application relevance and assess potential exposure.

Attack Path

How an attacker could exploit the issue

An unauthenticated attacker can exploit this vulnerability by sending specially crafted HTTP requests to the application's API. The attacker can bypass security checks by manipulating the `Origin` header and then provide malicious `host` and `port` values to the `/api/connect` endpoint. This allows the server to send outbound requests to attacker-controlled infrastructure, potentially leading to further compromise.

No authentication or network access required.
Triggered by crafting `Origin` and host/port headers.
Enables unauthenticated remote code execution.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability could allow an unauthenticated remote attacker to trick the Verba RAG application into making arbitrary HTTP requests to attacker-controlled infrastructure. This is possible by exploiting a server-side request forgery flaw combined with a same-origin middleware bypass, enabling the server to issue outbound GET requests when a crafted Origin header and attacker-controlled host and port values are supplied to the /api/connect endpoint.

Server-side request forgery.
Unauthenticated remote request execution.
Potential for reconnaissance or interaction with internal services.

Operational Fix

Recommended remediation, mitigation, and detection steps

The Verba RAG application's SSRF vulnerability requires immediate attention from application owners, platform teams, and security operations. The initial step is to locate all instances of the affected application, determine their reachability and business criticality, and assign ownership for remediation.

Identify application instances and assign ownership.
Verify external reachability and business impact.
Plan remediation with vendor and security teams.

Supplementary metadata

CVSS vector

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Frequently asked questions

What is Verba and how is it used?

Verba is a Retrieval-Augmented Generation (RAG) application. It is designed to bridge the gap between large language models and specific datasets, allowing users to query and retrieve information from private or specialized documents effectively. It is typically deployed as a web service or API to facilitate these search and interaction workflows.

What does CVE-2026-65317 mean for system security?

This vulnerability is a Server-Side Request Forgery (SSRF) combined with a middleware bypass. Essentially, it allows an unauthenticated user to trick the Verba application into making HTTP requests to destinations of the attacker's choosing. Because the application processes these requests on behalf of the user, it can be forced to interact with internal or external systems that the attacker might not be able to reach directly.

How do attackers trigger this vulnerability?

An attacker triggers this by sending a crafted HTTP request to the /api/connect endpoint. They bypass the application's origin security check by sending an Origin header prefixed with an apostrophe. Once this middleware check is bypassed, the attacker provides their own host and port parameters. Note that simply accessing the application home page or using standard search functions without these specific header manipulations does not trigger the bug.

Who should be concerned about CVE-2026-65317?

Anyone running the affected version of Verba should assess their risk. Halo Surface Signal notes that because Verba is a RAG application, it is often deployed as a web-facing service or API to support external users. If your instance is reachable from the internet, it is more likely to be targeted. Even internal instances should be reviewed if they reside in a network segment where unauthorized access to API endpoints is a concern.

How should I respond to this vulnerability?

The first step is to inventory your environment to locate all running instances of Verba version 2.1.3. Once identified, confirm the reachability of these instances and evaluate their business importance. Coordinate with your development and security teams to restrict access to the /api/connect endpoint and prepare for remediation steps provided by the software vendor to address the middleware and request handling flaws.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.