{"answers":{"affected":"3 open source packages ship an affected version, including github.com/modelcontextprotocol/registry.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-45781 exists.","fix":"Upgrade github.com/modelcontextprotocol/registry to 1.7.9 or later.","what":"CVE-2026-45781 is a low-severity vulnerability in modelcontextprotocol registry, published on 14 May 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-45781 and fix it if it is affected.\n\nWhat it is: CVE-2026-45781 is a low-severity vulnerability in modelcontextprotocol registry, published on 14 May 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-45781 exists.\n\nAffected packages and fixed versions:\n- github.com/modelcontextprotocol/registry (Go): affected all versions; fixed in 1.7.9\n- github.com/modelcontextprotocol/registry (Go): affected all versions; fixed in 1.7.9\n- github.com/modelcontextprotocol/registry (Go): affected all versions; fixed in 1.7.9\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-45781/ (Markdown: https://insights.sbomify.com/CVE-2026-45781/index.md)","id":"CVE-2026-45781","markdown":"https://insights.sbomify.com/CVE-2026-45781/index.md","name":"CVE-2026-45781","record":{"aliases":["GHSA-2v5f-5r6w-p67r","GO-2026-5008"],"analysis":{"component_type":"server_software","fix_type":"upgrade","impacts":["security_bypass","data_modify"],"network_reachable":"yes","non_default_config":false,"product_category":"MCP Registry","requires_auth":"low_privilege","summary":"Attackers can bypass OCI ownership validation during rate limits to claim unauthorized package namespaces in the MCP Registry.","user_interaction":"required","vuln_class":"security_feature_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[],"cvss":{"score":3.5,"severity":"low","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N","version":"3.1"},"cwes":[{"id":"CWE-636","name":"Not Failing Securely"}],"description":"The MCP Registry provides MCP clients with a list of MCP servers, like an app store for MCP servers. Prior to 1.7.9, OCI ownership validation skips label-match check when upstream OCI registry returns HTTP 429, letting any authenticated publisher bind their io.github.\u003cuser\u003e/* namespace to OCI images they do not control. internal/validators/registries/oci.go:104-119 fails open on http.StatusTooManyRequests: when the registry's anonymous fetch to the upstream OCI registry is rate-limited, ValidateOCI returns nil and the publish is accepted without ever running the io.modelcontextprotocol.server.name label-match check at lines 122-141. That label check is the only cross-system ownership proof the registry applies to OCI packages — every other registry type (NPM, PyPI, NuGet, MCPB) treats a non-200 upstream response as a hard error. This vulnerability is fixed in 1.7.9.","ecosystems":["Go"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"MCP Registry: OCI ownership validation fails open on upstream rate limits, allowing attacker-controlled package claims","id":"CVE-2026-45781","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Go","product":null,"products":[],"type":"security_feature_bypass","year":"2026"},"n_packages":3,"n_references":1,"next":{"headline":"Cloud Hypervisor: Use-after-free in virtio-block Async I/O Completion","id":"CVE-2026-45782"},"packages":[{"ecosystem":"Go","fixed":["1.7.9"],"introduced":["0"],"last_affected":[],"package":"github.com/modelcontextprotocol/registry","purl":null,"source":"GHSA-2v5f-5r6w-p67r"},{"ecosystem":"Go","fixed":["1.7.9"],"introduced":["0"],"last_affected":[],"package":"github.com/modelcontextprotocol/registry","purl":"pkg:golang/github.com/modelcontextprotocol/registry","source":"GHSA-2v5f-5r6w-p67r"},{"ecosystem":"Go","fixed":["1.7.9"],"introduced":["0"],"last_affected":[],"package":"github.com/modelcontextprotocol/registry","purl":"pkg:golang/github.com/modelcontextprotocol/registry","source":"GO-2026-5008"}],"prev":{"headline":"Discourse: Private event sample invitees are serialized to non-invited event viewers","id":"CVE-2026-45780"},"products":["registry"],"published":"2026-05-14","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"Go Vulnerability Database","prefix":"GO"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-16","vendors":["modelcontextprotocol"]},"summary":"Attackers can bypass OCI ownership validation during rate limits to claim unauthorized package namespaces in the MCP Registry.","url":"https://insights.sbomify.com/CVE-2026-45781/"}