{"api_version":"1","generated_at":"2026-09-23T09:57:08+00:00","cve":"CVE-2026-49446","urls":{"html":"https://cve.report/CVE-2026-49446","api":"https://cve.report/api/cve/CVE-2026-49446.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-49446","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-49446"},"summary":{"title":"Cosmos: Authentication bypass via forward-auth header smuggling on Constellation tunnel in Cosmos-Server","description":"Cosmos provides users the ability self-host a home server by acting as a secure gateway to your application, as well as a server manager. Prior to 0.22.19, tokenMiddleware in src/proxy/routerGen.go can return through the Constellation tunnel bypass before removing x-cosmos-user, x-cosmos-role, x-cosmos-user-role, and x-cosmos-mfa headers and before invoking AdminOnlyWithRedirect. An attacker with a valid x-cstln-auth API key for an enrolled device who reaches Cosmos through the Constellation Nebula tunnel can supply a chosen x-cosmos-user value to a route with AuthEnabled enabled when the upstream application trusts that forward-auth header. The request can bypass Cosmos JWT, password, MFA, and AdminOnly checks, allowing user impersonation and admin-tier reads or writes exposed by the proxied application. This issue is fixed in version 0.22.19.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2026-09-15 15:17:16","updated_at":"2026-09-15 15:17:16"},"problem_types":["CWE-285","CWE-290","CWE-285 CWE-285: Improper Authorization","CWE-290 CWE-290: Authentication Bypass by Spoofing"],"metrics":[{"version":"3.1","source":"security-advisories@github.com","type":"Secondary","score":"6.1","severity":"MEDIUM","vector":"CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N","baseScore":6.1,"baseSeverity":"MEDIUM","attackVector":"ADJACENT_NETWORK","attackComplexity":"LOW","privilegesRequired":"HIGH","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"NONE"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"6.1","severity":"MEDIUM","vector":"CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N","data":{"attackComplexity":"LOW","attackVector":"ADJACENT_NETWORK","availabilityImpact":"NONE","baseScore":6.1,"baseSeverity":"MEDIUM","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"HIGH","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N","version":"3.1"}}],"references":[{"url":"https://github.com/azukaar/Cosmos-Server/security/advisories/GHSA-2rx5-2g7j-2659","name":"https://github.com/azukaar/Cosmos-Server/security/advisories/GHSA-2rx5-2g7j-2659","refsource":"134c704f-9b21-4f2e-91b3-4a467353bcc0","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/azukaar/Cosmos-Server/commit/59c561d686c8f9843b3e092b50f6346c481d8bbf","name":"https://github.com/azukaar/Cosmos-Server/commit/59c561d686c8f9843b3e092b50f6346c481d8bbf","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/azukaar/Cosmos-Server/releases/tag/v0.22.19","name":"https://github.com/azukaar/Cosmos-Server/releases/tag/v0.22.19","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-49446","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-49446","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"azukaar","product":"Cosmos-Server","version":"affected < 0.22.19","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"metrics":[{"other":{"content":{"id":"CVE-2026-49446","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","timestamp":"2026-09-15T14:50:32.130417Z","version":"2.0.3"},"type":"ssvc"}}],"providerMetadata":{"dateUpdated":"2026-09-15T14:50:54.216Z","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP"},"references":[{"tags":["exploit"],"url":"https://github.com/azukaar/Cosmos-Server/security/advisories/GHSA-2rx5-2g7j-2659"}],"title":"CISA ADP Vulnrichment"}],"cna":{"affected":[{"product":"Cosmos-Server","vendor":"azukaar","versions":[{"status":"affected","version":"< 0.22.19"}]}],"descriptions":[{"lang":"en","value":"Cosmos provides users the ability self-host a home server by acting as a secure gateway to your application, as well as a server manager. Prior to 0.22.19, tokenMiddleware in src/proxy/routerGen.go can return through the Constellation tunnel bypass before removing x-cosmos-user, x-cosmos-role, x-cosmos-user-role, and x-cosmos-mfa headers and before invoking AdminOnlyWithRedirect. An attacker with a valid x-cstln-auth API key for an enrolled device who reaches Cosmos through the Constellation Nebula tunnel can supply a chosen x-cosmos-user value to a route with AuthEnabled enabled when the upstream application trusts that forward-auth header. The request can bypass Cosmos JWT, password, MFA, and AdminOnly checks, allowing user impersonation and admin-tier reads or writes exposed by the proxied application. This issue is fixed in version 0.22.19."}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"ADJACENT_NETWORK","availabilityImpact":"NONE","baseScore":6.1,"baseSeverity":"MEDIUM","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"HIGH","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-285","description":"CWE-285: Improper Authorization","lang":"en","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-290","description":"CWE-290: Authentication Bypass by Spoofing","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-09-15T14:31:24.778Z","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M"},"references":[{"name":"https://github.com/azukaar/Cosmos-Server/security/advisories/GHSA-2rx5-2g7j-2659","tags":["x_refsource_CONFIRM"],"url":"https://github.com/azukaar/Cosmos-Server/security/advisories/GHSA-2rx5-2g7j-2659"},{"name":"https://github.com/azukaar/Cosmos-Server/commit/59c561d686c8f9843b3e092b50f6346c481d8bbf","tags":["x_refsource_MISC"],"url":"https://github.com/azukaar/Cosmos-Server/commit/59c561d686c8f9843b3e092b50f6346c481d8bbf"},{"name":"https://github.com/azukaar/Cosmos-Server/releases/tag/v0.22.19","tags":["x_refsource_MISC"],"url":"https://github.com/azukaar/Cosmos-Server/releases/tag/v0.22.19"}],"source":{"advisory":"GHSA-2rx5-2g7j-2659","discovery":"UNKNOWN"},"title":"Cosmos: Authentication bypass via forward-auth header smuggling on Constellation tunnel in Cosmos-Server"}},"cveMetadata":{"assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","assignerShortName":"GitHub_M","cveId":"CVE-2026-49446","datePublished":"2026-09-15T14:31:24.778Z","dateReserved":"2026-05-30T02:43:33.106Z","dateUpdated":"2026-09-15T14:50:54.216Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-15 15:17:16","lastModifiedDate":"2026-09-15 15:17:16","problem_types":["CWE-285","CWE-290","CWE-285 CWE-285: Improper Authorization","CWE-290 CWE-290: Authentication Bypass by Spoofing"],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N","baseScore":6.1,"baseSeverity":"MEDIUM","attackVector":"ADJACENT_NETWORK","attackComplexity":"LOW","privilegesRequired":"HIGH","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"NONE"},"exploitabilityScore":0.9,"impactScore":5.2}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-09-15T14:50:32.130417Z","id":"CVE-2026-49446","options":[{"exploitation":"poc"},{"automatable":"no"},{"technicalImpact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"49446","Ordinal":"1","Title":"Cosmos: Authentication bypass via forward-auth header smuggling ","CVE":"CVE-2026-49446","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"49446","Ordinal":"1","NoteData":"Cosmos provides users the ability self-host a home server by acting as a secure gateway to your application, as well as a server manager. Prior to 0.22.19, tokenMiddleware in src/proxy/routerGen.go can return through the Constellation tunnel bypass before removing x-cosmos-user, x-cosmos-role, x-cosmos-user-role, and x-cosmos-mfa headers and before invoking AdminOnlyWithRedirect. An attacker with a valid x-cstln-auth API key for an enrolled device who reaches Cosmos through the Constellation Nebula tunnel can supply a chosen x-cosmos-user value to a route with AuthEnabled enabled when the upstream application trusts that forward-auth header. The request can bypass Cosmos JWT, password, MFA, and AdminOnly checks, allowing user impersonation and admin-tier reads or writes exposed by the proxied application. This issue is fixed in version 0.22.19.","Type":"Description","Title":"Cosmos: Authentication bypass via forward-auth header smuggling "}]}}}