{ "document": { "category": "csaf_base", "csaf_version": "2.0", "distribution": { "tlp": { "label": "WHITE" } }, "lang": "en", "notes": [ { "category": "legal_disclaimer", "text": "The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this portal to enhance access to its information and vulnerabilities. The use of this information is subject to the following terms and conditions:\n\nThe vulnerabilities disclosed in this portal are gathered by NCSC-NL from a variety of open sources, which the user can retrieve from other platforms. NCSC-NL makes every reasonable effort to ensure that the content of this portal is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or real-time keeping up-to-date. NCSC-NL does not control nor guarantee the accuracy, relevance, timeliness or completeness of information obtained from these external sources. The vulnerabilities disclosed in this portal are intended solely for the convenience of professional parties to take appropriate measures to manage the risks posed to the cybersecurity. No rights can be derived from the information provided therein.\n\nNCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of the vulnerabilities disclosed in this portal. This includes damage resulting from the inaccuracy of incompleteness of the information contained in it.\nThe information on this page is subject to Dutch law. All disputes related to or arising from the use of this portal regarding the disclosure of vulnerabilities will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings." } ], "publisher": { "category": "coordinator", "contact_details": "cert@ncsc.nl", "name": "National Cyber Security Centre", "namespace": "https://www.ncsc.nl/" }, "title": "CVE-2026-34742", "tracking": { "current_release_date": "2026-04-03T16:39:54.191218Z", "generator": { "date": "2026-02-17T15:00:00Z", "engine": { "name": "V.E.L.M.A", "version": "1.7" } }, "id": "CVE-2026-34742", "initial_release_date": "2026-04-01T22:11:13.214166Z", "revision_history": [ { "date": "2026-04-01T22:11:13.214166Z", "number": "1", "summary": "CVE created.| Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (2).| CWES updated (1)." }, { "date": "2026-04-01T22:11:20.708086Z", "number": "2", "summary": "NCSC Score created." }, { "date": "2026-04-02T19:39:50.139704Z", "number": "3", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products created (1).| References created (4).| CWES updated (1)." }, { "date": "2026-04-02T19:39:52.087918Z", "number": "4", "summary": "NCSC Score updated." }, { "date": "2026-04-02T20:10:24.221954Z", "number": "5", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (4).| CWES updated (1)." }, { "date": "2026-04-02T20:10:25.581973Z", "number": "6", "summary": "NCSC Score updated." }, { "date": "2026-04-03T00:27:49.961570Z", "number": "7", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (14).| Product Identifiers created (5).| Product Remediations created (14).| References created (6).| CWES updated (1).| Vendor_assessment created." }, { "date": "2026-04-03T00:28:00.703726Z", "number": "8", "summary": "NCSC Score updated." }, { "date": "2026-04-03T07:35:29.568122Z", "number": "9", "summary": "NCSC Score updated." }, { "date": "2026-04-03T15:31:04.224291Z", "number": "10", "summary": "Source connected.| CVE status created. (valid)| EPSS created." }, { "date": "2026-04-03T15:31:06.539055Z", "number": "11", "summary": "NCSC Score updated." }, { "date": "2026-04-03T16:38:48.450521Z", "number": "12", "summary": "Unknown change." } ], "status": "interim", "version": "12" } }, "product_tree": { "branches": [ { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:rpm/2", "product": { "name": "vers:rpm/2", "product_id": "CSAFPID-1919968", "product_identification_helper": { "cpe": "cpe:/a:redhat:migration_toolkit_virtualization:2" } } } ], "category": "product_name", "name": "Migration Toolkit for Virtualization" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-2524222", "product_identification_helper": { "cpe": "cpe:/a:redhat:openshift_lightspeed" } } } ], "category": "product_name", "name": "OpenShift Lightspeed" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/1", "product": { "name": "vers:rpm/1", "product_id": "CSAFPID-1441076", "product_identification_helper": { "cpe": "cpe:/a:redhat:serverless:1" } } } ], "category": "product_name", "name": "OpenShift Serverless" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-1439279", "product_identification_helper": { "cpe": "cpe:/a:redhat:openshift_ai" } } } ], "category": "product_name", "name": "Red Hat OpenShift AI (RHOAI)" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/3", "product": { "name": "vers:rpm/3", "product_id": "CSAFPID-1441150", "product_identification_helper": { "cpe": "cpe:/a:redhat:openshift_devspaces:3:" } } } ], "category": "product_name", "name": "Red Hat OpenShift Dev Spaces" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-5597158" } } ], "category": "product_name", "name": "kn-client-kn-rhel9" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-5207394" } } ], "category": "product_name", "name": "kn-plugin-func-func-util-rhel9" } ], "category": "product_family", "name": "OpenShift Serverless" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-1496183" } } ], "category": "product_name", "name": "mtv-api-rhel9" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-5736836" } } ], "category": "product_name", "name": "mtv-cli-download-rhel9" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-2485095" } } ], "category": "product_name", "name": "mtv-controller-rhel9" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-5736837" } } ], "category": "product_name", "name": "mtv-operator-bundle" } ], "category": "product_family", "name": "Migration Toolkit for Virtualization" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-5222758" } } ], "category": "product_name", "name": "odh-mod-arch-gen-ai-rhel9" } ], "category": "product_family", "name": "Red Hat OpenShift AI (RHOAI)" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-5157306" } } ], "category": "product_name", "name": "openshift-mcp-server-rhel9" } ], "category": "product_family", "name": "OpenShift Lightspeed" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-2652733" } } ], "category": "product_name", "name": "udi-rhel9" } ], "category": "product_family", "name": "Red Hat OpenShift Dev Spaces" } ], "category": "vendor", "name": "Red Hat" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/<1.4.0", "product": { "name": "vers:unknown/<1.4.0", "product_id": "CSAFPID-5985309" } } ], "category": "product_name", "name": "go-sdk" } ], "category": "vendor", "name": "modelcontextprotocol" } ] }, "vulnerabilities": [ { "cve": "CVE-2026-34742", "cwe": { "id": "CWE-1188", "name": "Initialization of a Resource with an Insecure Default" }, "notes": [ { "category": "description", "text": "The Model Context Protocol (MCP) Go SDK does not enable DNS rebinding protection by default for HTTP-based servers. When an HTTP-based MCP server is run on localhost without authentication with `StreamableHTTPHandler` or `SSEHandler`, a malicious website could exploit DNS rebinding to bypass same-origin policy restrictions and send requests to the local MCP server. This could allow an attacker to invoke tools or access resources exposed by the MCP server on behalf of the user in those limited circumstances.\n\nNote that running HTTP-based MCP servers locally without authentication is not recommended per MCP security best practices. This issue does not affect servers using stdio transport.\n\nServers created via `StreamableHTTPHandler` or `SSEHandler` now have this protection enabled by default when binding to `localhost`. Users are advised to update to version `1.4.0` to receive this automatic protection.", "title": "github - https://api.github.com/advisories/GHSA-xw59-hvm2-8pj6" }, { "category": "description", "text": "The Go MCP SDK used Go's standard encoding/json. Prior to version 1.4.0, the Model Context Protocol (MCP) Go SDK does not enable DNS rebinding protection by default for HTTP-based servers. When an HTTP-based MCP server is run on localhost without authentication with StreamableHTTPHandler or SSEHandler, a malicious website could exploit DNS rebinding to bypass same-origin policy restrictions and send requests to the local MCP server. This could allow an attacker to invoke tools or access resources exposed by the MCP server on behalf of the user in those limited circumstances. This issue has been patched in version 1.4.0.", "title": "cveprojectv5 - https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/34xxx/CVE-2026-34742.json" }, { "category": "description", "text": "The Go MCP SDK used Go's standard encoding/json. Prior to version 1.4.0, the Model Context Protocol (MCP) Go SDK does not enable DNS rebinding protection by default for HTTP-based servers. When an HTTP-based MCP server is run on localhost without authentication with StreamableHTTPHandler or SSEHandler, a malicious website could exploit DNS rebinding to bypass same-origin policy restrictions and send requests to the local MCP server. This could allow an attacker to invoke tools or access resources exposed by the MCP server on behalf of the user in those limited circumstances. This issue has been patched in version 1.4.0.", "title": "nvd - https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-34742" }, { "category": "description", "text": "A flaw was found in the Model Context Protocol (MCP) Go SDK. When an HTTP-based MCP server is run on localhost without authentication, a malicious website can exploit a DNS rebinding vulnerability. This allows the attacker to bypass same-origin policy restrictions and send requests to the local MCP server. Consequently, an attacker could invoke tools or access resources exposed by the MCP server on behalf of the user.", "title": "redhat - https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-34742.json" }, { "category": "other", "text": "0.0008", "title": "EPSS" }, { "category": "other", "text": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N", "title": "CVSSV4" }, { "category": "other", "text": "7.6", "title": "CVSSV4 base score" }, { "category": "other", "text": "4.1", "title": "NCSC Score" }, { "category": "other", "text": "The value of the most recent EPSS score", "title": "NCSC Score top decreasing factors" }, { "category": "details", "text": "Severity: 3\n", "title": "Vendor assessment" } ], "product_status": { "known_affected": [ "CSAFPID-5985309", "CSAFPID-1439279", "CSAFPID-1441076", "CSAFPID-1441150", "CSAFPID-1496183", "CSAFPID-1919968", "CSAFPID-2485095", "CSAFPID-2524222", "CSAFPID-2652733", "CSAFPID-5157306", "CSAFPID-5207394", "CSAFPID-5222758", "CSAFPID-5597158", "CSAFPID-5736836", "CSAFPID-5736837" ] }, "references": [ { "category": "external", "summary": "Source - github", "url": "https://api.github.com/advisories/GHSA-xw59-hvm2-8pj6" }, { "category": "external", "summary": "Source - cveprojectv5", "url": "https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/34xxx/CVE-2026-34742.json" }, { "category": "external", "summary": "Source - nvd", "url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-34742" }, { "category": "external", "summary": "Source - redhat", "url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-34742.json" }, { "category": "external", "summary": "Source - first", "url": "https://api.first.org/data/v1/epss?limit=10000&offset=0" }, { "category": "external", "summary": "Reference - cveprojectv5; github; nvd; redhat", "url": "https://github.com/modelcontextprotocol/go-sdk/security/advisories/GHSA-xw59-hvm2-8pj6" }, { "category": "external", "summary": "Reference - github", "url": "https://github.com/advisories/GHSA-xw59-hvm2-8pj6" }, { "category": "external", "summary": "Reference - cveprojectv5; nvd; redhat", "url": "https://github.com/modelcontextprotocol/go-sdk/pull/760" }, { "category": "external", "summary": "Reference - cveprojectv5; nvd; redhat", "url": "https://github.com/modelcontextprotocol/go-sdk/commit/67bd3f2e2b53ce11a16db8d976cdb8ff1e986b6d" }, { "category": "external", "summary": "Reference - cveprojectv5; nvd; redhat", "url": "https://github.com/modelcontextprotocol/go-sdk/releases/tag/v1.4.0" }, { "category": "external", "summary": "Reference - redhat", "url": "https://www.cve.org/CVERecord?id=CVE-2026-34742" }, { "category": "external", "summary": "Reference - redhat", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34742" } ], "remediations": [ { "category": "mitigation", "details": "Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.", "product_ids": [ "CSAFPID-1439279", "CSAFPID-1441076", "CSAFPID-1441150", "CSAFPID-1496183", "CSAFPID-1919968", "CSAFPID-2485095", "CSAFPID-2524222", "CSAFPID-2652733", "CSAFPID-5157306", "CSAFPID-5207394", "CSAFPID-5222758", "CSAFPID-5597158", "CSAFPID-5736836", "CSAFPID-5736837" ] } ], "scores": [ { "cvss_v3": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N", "baseScore": 8.0, "baseSeverity": "HIGH" }, "products": [ "CSAFPID-1439279", "CSAFPID-1441076", "CSAFPID-1441150", "CSAFPID-1496183", "CSAFPID-1919968", "CSAFPID-2485095", "CSAFPID-2524222", "CSAFPID-2652733", "CSAFPID-5157306", "CSAFPID-5207394", "CSAFPID-5222758", "CSAFPID-5597158", "CSAFPID-5736836", "CSAFPID-5736837", "CSAFPID-5985309" ] } ], "title": "CVE-2026-34742" } ] }