{"id":"EUVD-2026-81899","revision":null,"records":[{"revision":"53e92bf3e1cc47f9a55119a1064e52a9","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-81868","aliases":[],"title":"Steeltoe: Header-forwarded client cert lacks proof of private-key possession","description":"Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. Prior to 4.3.0, Steeltoe.Security.Authorization.Certificate deployments using AddOrgAndSpacePolicies() and UseCertificateAuthorization() trust the public certificate supplied in the X-Client-Cert request header without proving possession of the corresponding private key. Common Cloud Foundry routers do not remove this header from inbound requests. When inbound requests are not restricted to a known trusted proxy source IP, an attacker who obtains the public certificate of an application instance in the target organization or space and can reach the application can spoof X-Client-Cert to bypass the SameOrg and SameSpace policies for the certificate validity period. This issue is fixed in version 4.3.0.","state":0,"publishedAt":"2026-09-17T15:36:23.149+00:00","modifiedAt":"2026-09-23T18:46:54.265+00:00","affected":[{"ecosystem":"Vendor product","name":"security-advisories","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"SteeltoeOSS\",\n                    \"product\": \"security-advisories\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 4.3.0\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","score":6.5,"severity":"MEDIUM"}],"references":["https://github.com/SteeltoeOSS/security-advisories/security/advisories/GHSA-5mq7-rwhj-4fh9","https://github.com/SteeltoeOSS/Steeltoe/commit/b626ef3d60aaf19c68eeeed5ee81045406c8c6d0","https://github.com/SteeltoeOSS/Steeltoe/releases/tag/4.3.0"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-81868","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-81868","identifiers":["CVE-2026-81868"]},"retained":false,"historicalAffected":[]},{"revision":"898761fa92384f5e82a79a50195f4bf4","observedAt":"2026-11-11T16:10:28.014+00:00","statement":{"source":"euvd","id":"EUVD-2026-81899","aliases":["CVE-2026-81868","GHSA-5mq7-rwhj-4fh9"],"title":"Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. 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This issue is fixed in version 4.3.0.","state":0,"publishedAt":null,"modifiedAt":null,"affected":[],"metrics":[{"system":"EUVD CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","score":6.5,"severity":null}],"references":["https://github.com/SteeltoeOSS/security-advisories/security/advisories/GHSA-5mq7-rwhj-4fh9","https://github.com/SteeltoeOSS/Steeltoe/commit/b626ef3d60aaf19c68eeeed5ee81045406c8c6d0","https://github.com/SteeltoeOSS/Steeltoe/releases/tag/4.3.0"],"sourceUrl":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-81899","license":"ENISA EUVD · source terms and attribution apply","enrichment":{"sourceStatus":null,"weaknesses":[],"productCriteria":[],"sourceDates":{"datePublished":"Sep 17, 2026, 3:36:23 PM","dateUpdated":"Sep 23, 2026, 6:46:54 PM"},"relatedAdvisories":[],"note":"EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON."},"key":"euvd:EUVD-2026-81899","identifiers":["EUVD-2026-81899","CVE-2026-81868","GHSA-5mq7-rwhj-4fh9"]},"retained":false,"historicalAffected":[]},{"revision":"55d4bad8f8754370b0ed94e4c08d1ea8","observedAt":"2026-10-25T16:19:10.271+00:00","statement":{"source":"nvd","id":"CVE-2026-81868","aliases":[],"title":"Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. Prior to 4.3.0, Steeltoe.Security.Authorization.Certificate deployments using AddOrgAndSpacePolicies() and UseCerti…","description":"Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. Prior to 4.3.0, Steeltoe.Security.Authorization.Certificate deployments using AddOrgAndSpacePolicies() and UseCertificateAuthorization() trust the public certificate supplied in the X-Client-Cert request header without proving possession of the corresponding private key. Common Cloud Foundry routers do not remove this header from inbound requests. When inbound requests are not restricted to a known trusted proxy source IP, an attacker who obtains the public certificate of an application instance in the target organization or space and can reach the application can spoof X-Client-Cert to bypass the SameOrg and SameSpace policies for the certificate validity period. This issue is fixed in version 4.3.0.","state":0,"publishedAt":"2026-09-17T16:17:47.607+00:00","modifiedAt":"2026-09-30T17:31:44.573+00:00","affected":[],"metrics":[{"system":"CVSS 3.1 · security-advisories@github.com · Secondary","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","score":6.5,"severity":"MEDIUM"}],"references":["https://github.com/SteeltoeOSS/Steeltoe/commit/b626ef3d60aaf19c68eeeed5ee81045406c8c6d0","https://github.com/SteeltoeOSS/Steeltoe/releases/tag/4.3.0","https://github.com/SteeltoeOSS/security-advisories/security/advisories/GHSA-5mq7-rwhj-4fh9"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-81868","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Awaiting Analysis","weaknesses":["CWE-288","CWE-295"],"productCriteria":[],"sourceDates":{"published":"2026-09-17T16:17:47.607","lastModified":"2026-09-30T17:31:44.573"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-81868","identifiers":["CVE-2026-81868"]},"retained":false,"historicalAffected":[]},{"revision":"2450f243545b4129a50cfbe7b6993844","observedAt":"2026-10-23T16:01:25.029+00:00","statement":{"source":"osv","id":"GHSA-5mq7-rwhj-4fh9","aliases":["CVE-2026-81868"],"title":"Steeltoe: Header-forwarded client cert lacks proof of private-key possession","description":"### Summary\n\nWhen Steeltoe's certificate-based authorization (`UseCertificateAuthorization`) is configured, the default configuration of the middleware relies on the `X-Client-Cert` HTTP header to identify the client certificate, without verifying private-key possession. This header is not stripped by common Cloud Foundry routers (like Gorouter or Envoy) on inbound requests.\n\n### Impact\n\nAn attacker who obtains the public certificate of an application instance in the target organization or space can spoof the `X-Client-Cert` header. This allows the attacker to bypass `SameOrg` and `SameSpace` authorization policies, granting unauthorized access to protected endpoints for the duration of the certificate's validity period.\n\n### Affected configuration\n\n- The application uses `AddOrgAndSpacePolicies()` and `UseCertificateAuthorization()` for inter-service authorization.\n- Inbound requests are not restricted to a known trusted proxy source IP.\n- The application's endpoints are network-accessible to the attacker (e.g., exposed to the internet via a public Cloud Foundry route, or the attacker has access to the internal Cloud Foundry network).\n\n### Mitigations\n\nIf an immediate upgrade to a patched version is not possible:\n\n- Restrict `UseCertificateForwarding` to trusted proxy source IPs using `ForwardedHeadersOptions.KnownProxies` and `KnownNetworks`.\n- Change the forwarding header to `X-Forwarded-Client-Cert` so that Cloud Foundry Gorouter and Envoy header stripping mechanisms apply to inbound untrusted requests.\n- Add a secondary authorization layer (e.g., a shared secret or mutual TLS at the proxy layer) for sensitive endpoints.\n- Ensure the application is not bound to a public route unless explicitly required. Use Cloud Foundry internal routes (e.g., `.apps.internal`) and container-to-container network policies to strictly limit network access to intended internal clients.","state":0,"publishedAt":"2026-09-17T20:30:58+00:00","modifiedAt":"2026-09-17T20:45:06.0601928+00:00","affected":[{"ecosystem":"NuGet","name":"Steeltoe.Security.Authorization.Certificate","ranges":[{"type":"ECOSYSTEM","events":[{"kind":"introduced","version":"0"},{"kind":"fixed","version":"4.3.0"}]}],"versions":["4.0.0","4.0.0-beta1","4.0.0-rc1","4.1.0","4.2.0"],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V3","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"MODERATE"}],"references":["https://github.com/SteeltoeOSS/security-advisories/security/advisories/GHSA-5mq7-rwhj-4fh9","https://nvd.nist.gov/vuln/detail/CVE-2026-81868","https://github.com/SteeltoeOSS/Steeltoe/commit/b626ef3d60aaf19c68eeeed5ee81045406c8c6d0","https://github.com/SteeltoeOSS/Steeltoe/releases/tag/4.3.0","https://github.com/SteeltoeOSS/security-advisories"],"sourceUrl":"https://github.com/advisories/GHSA-5mq7-rwhj-4fh9","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-5mq7-rwhj-4fh9","identifiers":["GHSA-5mq7-rwhj-4fh9","CVE-2026-81868"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-11-12T02:56:45.8822264+00:00","complete":true,"records":1779,"lastAttemptAt":"2026-11-12T02:56:45.8822264+00:00","lastSuccessAt":"2026-11-12T02:56:46.0427292+00:00","error":null,"lastVerifiedAt":"2026-11-12T02:56:46.0427301+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"cve-program","scope":"Official CVE Program baseline and cumulative hourly delta; all vendors, published and rejected records","generation":"cve-64752486c567b55b31fb0d7225f5222bcd0019564ac0ac5f0649e242c7b19299-c8f0a5eb97b437649f83f6fe632ec849fcb249052407d33e475e82c88b318dfb","complete":true,"records":424535,"lastAttemptAt":"2026-11-12T02:56:45.3610802+00:00","lastSuccessAt":"2026-11-12T02:56:45.341976+00:00","error":null,"lastVerifiedAt":"2026-11-12T02:56:45.3610802+00:00","snapshotPublishedAt":"2026-11-12T02:25:26+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"euvd","scope":"Rolling EUVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global EUVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-3bce114846604d92838a2dc302341627","complete":false,"records":13760,"lastAttemptAt":"2026-11-12T03:06:53.8778262+00:00","lastSuccessAt":"2026-11-12T03:06:52.8+00:00","error":"754 identifier lookups failed; latest failures include AccessDenied (HTTP 403). Other identifiers were checked independently.","lastVerifiedAt":"2026-11-12T03:06:52.8+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13040,"expectedIdentifiers":13813,"failedIdentifiers":754},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. 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