CVE WatchJul 15, 2026

CVE-2026-27896

The Go MCP SDK used Go's standard encoding/json.Unmarshal for JSON-RPC and MCP protocol message parsing in versions prior to 1.3.1. Go's sta

CVSS

7.5

High

EPSS

0.3%

p17

KEV

—

Exploit Today

0-100

Published: Feb 26, 2026 · Last modified: Jul 15, 2026 · CWE-178 · CWE-436

EPSS · 30d

0.3%EPSS · 30 days0.3%

2026-06-302026-07-20

Technical description

The Go MCP SDK used Go's standard encoding/json.Unmarshal for JSON-RPC and MCP protocol message parsing in versions prior to 1.3.1. Go's standard library performs case-insensitive matching of JSON keys to struct field tags — a field tagged json:"method" would also match "Method", "METHOD", etc. This violated the JSON-RPC 2.0 specification, which defines exact field names. A malicious MCP peer may have been able to send protocol messages with non-standard field casing that the SDK would silently accept. This had the potential for bypassing intermediary inspection and coss-implementation inconsistency. Go's standard JSON unmarshaling was replaced with a case-sensitive decoder in commit 7b8d81c. Users are advised to update to v1.3.1 to resolve this issue.

Official references

Related CVEs

CVECVSSEPSSKEVRExploitTitleMod.

CVE-2026-630309.8 CRI

94.7%

——28WordPress 6.9.x before 6.9.5 and 7.0.x before 7.0.2 is affected by a REST API batch endpoint route confusion issue which, combined with the author__not_in WP_Query SQL Injection (CVE-2026-60137), could allow an attacker to perform SQL Injection and achieve Remote Code Execution.3d CVE-2026-473239.8 CRI

70.0%

——21Camel-CXF and Camel-Knative Message Header Injection via Missing Inbound Filtering The CXF and Knative HeaderFilterStrategy implementations (CxfRsHeaderFilterStrategy in camel-cxf-rest, CxfHeaderFilterStrategy in camel-cxf-transport, and KnativeHttpHeaderFilterStrategy in camel-knative-http) only filter outbound Camel-internal headers via setOutFilterStartsWith, while not configuring inbound filtering via setInFilterStartsWith. As a result, an unauthenticated attacker can inject Camel-internal headers (e.g. CamelExecCommandExecutable, CamelFileName) via HTTP requests to CXF-RS or CXF-SOAP endpoints. When a route forwards messages from these endpoints to header-driven components such as camel-exec or camel-file, the injected headers override configured values, enabling remote code execution or arbitrary file writes. This is the same pattern that was previously addressed in camel-undertow (CVE-2025-30177), the broader incoming-header filter (CVE-2025-27636 and CVE-2025-29891), and non-HTTP strategies (CVE-2026-40453). This issue affects Apache Camel: from 3.18.0 before 4.14.6, from 4.15.0 before 4.18.2. Users are recommended to upgrade to version 4.19.0, which fixes the issue. If users are on the 4.18.x LTS releases stream, then they are suggested to upgrade to 4.18.2. If users are on the 4.14.x LTS releases stream, then they are suggested to upgrade to 4.14.6.6d CVE-2026-282929.8 CRI

67.2%

——20`simple-git`, an interface for running git commands in any node.js application, has an issue in versions 3.15.0 through 3.32.2 that allows an attacker to bypass two prior CVE fixes (CVE-2022-25860 and CVE-2022-25912) and achieve full remote code execution on the host machine. Version 3.23.0 contains an updated fix for the vulnerability.6d CVE-2026-404539.9 CRI

54.5%

——16The fix for CVE-2025-27636 added setLowerCase(true) to HttpHeaderFilterStrategy so that case-variant header names such as 'CAmelExecCommandExecutable' are filtered out alongside 'CamelExecCommandExecutable'. The same setLowerCase(true) call was not applied to five non-HTTP HeaderFilterStrategy implementations: JmsHeaderFilterStrategy and ClassicJmsHeaderFilterStrategy in camel-jms, SjmsHeaderFilterStrategy in camel-sjms, CoAPHeaderFilterStrategy in camel-coap, and GooglePubsubHeaderFilterStrategy in camel-google-pubsub. Because those strategies use case-sensitive String.startsWith('Camel'/'camel') filtering while the Camel Exchange stores headers in a case-insensitive map, an attacker with JMS (or equivalent) producer access to the broker consumed by a Camel route can inject case-variant Camel internal headers, which are then resolved by downstream components such as camel-exec and camel-file using their canonical casing. This enables remote code execution and arbitrary file write on routes that forward JMS messages to header-driven components. This issue affects Apache Camel: from 3.0.0 before 4.14.6, from 4.15.0 before 4.18.2, from 4.19.0 before 4.20.0. Users are recommended to upgrade to version 4.20.0, which fixes the issue. If users are on the 4.14.x LTS releases stream, then they are suggested to upgrade to 4.14.6. If users are on the 4.18.x releases stream, then they are suggested to upgrade to 4.18.2.6d CVE-2026-580575.0 MED

53.4%

——16Flowise before 3.1.3 validates Custom MCP stdio environment variables against a denylist using a case-sensitive comparison, so on Windows, where environment names are case-insensitive, supplying 'node_options' bypasses the NODE_OPTIONS denylist entry. An authenticated user who can configure a Custom MCP node can thereby inject NODE_OPTIONS --require and execute arbitrary code in the Flowise server context.15d CVE-2026-252237.5 HIG

51.6%

——15Fastify is a fast and low overhead web framework, for Node.js. Prior to version 5.7.2, a validation bypass vulnerability exists in Fastify where request body validation schemas specified by Content-Type can be completely circumvented. By appending a tab character (\t) followed by arbitrary content to the Content-Type header, attackers can bypass body validation while the server still processes the body as the original content type. This issue has been patched in version 5.7.2.6d