CVE-2026-39885 | agentfront frontmcp/adapters/sdk/mcp-from-openapi Model Context Protocol initialize ref server-side request forgery (GHSA-v6ph-xcq9-qxxj)

VDB-356497 · CVE-2026-39885 · GHSA-V6PH-XCQ9-QXXJ AGENTFRONT FRONTMCP/ADAPTERS/SDK/MCP-FROM-OPENAPI MODEL CONTEXT PROTOCOL INITIALIZE REF SERVER-SIDE REQUEST FORGERY HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 7.2 $0-$5k 2.79 Summaryinfo A vulnerability, which was classified as critical, has been found in agentfront frontmcp, adapters, sdk and mcp-from-openapi. This impacts the function initialize of the component Model Context Protocol. This manipulation of the argument ref causes server-side request forgery. This vulnerability is tracked as CVE-2026-39885. The attack is possible to be carried out remotely. No exploit exists. It is advisable to upgrade the affected component. Detailsinfo A vulnerability was found in agentfront frontmcp, adapters, sdk and mcp-from-openapi (affected version unknown). It has been declared as critical. Affected by this vulnerability is the function initialize of the component Model Context Protocol. The manipulation of the argument ref with an unknown input leads to a server-side request forgery vulnerability. The CWE definition for the vulnerability is CWE-918. The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is: FrontMCP is a TypeScript-first framework for the Model Context Protocol (MCP). Prior to 2.3.0, the mcp-from-openapi library uses @apidevtools/json-schema-ref-parser to dereference $ref pointers in OpenAPI specifications without configuring any URL restrictions or custom resolvers. A malicious OpenAPI specification containing $ref values pointing to internal network addresses, cloud metadata endpoints, or local files will cause the library to fetch those resources during the initialize() call. This enables Server-Side Request Forgery (SSRF) and local file read attacks when processing untrusted OpenAPI specifications. This vulnerability is fixed in 2.3.0. The advisory is shared at github.com. This vulnerability is known as CVE-2026-39885 since 04/07/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available. Upgrading eliminates this vulnerability. Productinfo Type Artificial Intelligence Software Vendor agentfront Name adapters frontmcp mcp-from-openapi sdk Website Product: https://github.com/agentfront/frontmcp/ CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 7.4 VulDB Meta Temp Score: 7.2 VulDB Base Score: 7.3 VulDB Temp Score: 7.0 VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA Base Score: 7.5 CNA Vector (GitHub_M): 🔒 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Server-side request forgery CWE: CWE-918 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: Upgrade Status: 🔍 0-Day Time: 🔒 Timelineinfo 04/07/2026 CVE reserved 04/09/2026 +2 days Advisory disclosed 04/09/2026 +0 days VulDB entry created 04/09/2026 +0 days VulDB entry last update Sourcesinfo Product: github.com Advisory: GHSA-v6ph-xcq9-qxxj Status: Confirmed CVE: CVE-2026-39885 (🔒) GCVE (CVE): GCVE-0-2026-39885 GCVE (VulDB): GCVE-100-356497 Entryinfo Created: 04/09/2026 02:51 Changes: 04/09/2026 02:51 (66) Complete: 🔍 Cache ID: 99:FE1:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸