CVE-2026-6790: Eclipse Jetty HTTP Authority/Host Mismatch Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-7p3p-8qv8-m2vh",
  "modified" : "2026-07-22T22:56:43Z",
  "published" : "2026-07-22T22:56:43Z",
  "aliases" : [ "CVE-2026-6790" ],
  "summary" : "Eclipse Jetty: HTTP Authority/Host mismatch",
  "details" : "#### Summary\n\nJetty currently accepts HTTP/2 and HTTP/3 requests where the regular\nHost header and the pseudo-header :authority\ndo not match. As a result, the same request can carry two different host identities\nthrough Jetty:\n\n- logic based on `HttpURI` / `Request.getServerName(request)` uses `:authority`\n- logic based on raw request headers continues to use `Host`\n\nThis creates a host/authority confusion condition that can break\nsecurity assumptions in higher layers.\n\nJetty already performs an explicit authority/Host consistency check on\nthe HTTP/1.1 path, but equivalent validation is missing on the HTTP/2\nand HTTP/3 paths.\n\n#### Security Impact\n\nThis issue is not inherently remote code execution, but it can become\nsecurity-relevant in deployments that rely on the request host for\nsecurity-sensitive decisions, including:\n\n- host-based access control\n- virtual host isolation\n- multi-tenant routing by hostname\n- login/logout/callback URL construction\n- reverse proxy and forwarded-header trust chains\n- auditing, cache keys, and absolute URL generation\n\nPotential consequences include:\n\n- bypass of host-based ACLs\n- virtual host or tenant isolation failures\n- incorrect or attacker-influenced redirect/callback targets\n- inconsistent proxy/downstream interpretation of the original target host\n- misleading logs and audit records\n\n#### Technical Root Cause\n\n1. On the HTTP/2 and HTTP/3 metadata builder paths:\n\n- `:authority` is parsed separately into authority/URI state\n- `Host` is preserved as a normal request header\n- the two values are not compared for consistency\n\n2. On the HTTP/2 and HTTP/3 server entry paths:\n\n- Jetty calls `ComplianceUtils.verify(httpCompliance, requestMetaData, listener)`\n- this verification does not enforce `MISMATCHED_AUTHORITY`\n\n3. On the HTTP/1.1 path:\n\n- Jetty explicitly checks whether authority and `Host` match\n- mismatches are rejected by default\n\n#### Relevant Code Locations\n\nHTTP/2 metadata builder:\n\n- `jetty-core/jetty-http2/jetty-http2-hpack/src/main/java/org/eclipse/jetty/http2/hpack/internal/MetaDataBuilder.java`\n\nHTTP/3 metadata builder:\n\n- `jetty-core/jetty-http3/jetty-http3-qpack/src/main/java/org/eclipse/jetty/http3/qpack/internal/metadata/MetaDataBuilder.java`\n\nHTTP/2 server entry:\n\n- `jetty-core/jetty-http2/jetty-http2-server/src/main/java/org/eclipse/jetty/http2/server/internal/HttpStreamOverHTTP2.java`\n\nHTTP/3 server entry:\n\n- `jetty-core/jetty-http3/jetty-http3-server/src/main/java/org/eclipse/jetty/http3/server/internal/HttpStreamOverHTTP3.java`\n\nShared HTTP compliance verification:\n\n- `jetty-core/jetty-http/src/main/java/org/eclipse/jetty/http/ComplianceUtils.java`\n\nHTTP/1.1 authority/Host consistency check:\n\n- `jetty-core/jetty-server/src/main/java/org/eclipse/jetty/server/internal/HttpConnection.java`\n\nDefined but not enforced on H2/H3:\n\n- `jetty-core/jetty-http/src/main/java/org/eclipse/jetty/http/HttpCompliance.java`\n- violation: MISMATCHED_AUTHORITY\n\n#### Reproduction\n\nI reproduced this on local Jetty 12.1.9-SNAPSHOT source.\n\nMinimal reproduction steps:\n\n1. Start a Jetty HTTP/2 or HTTP/3 test server.\n2. Send a request with:\n    - :authority = localhost:<port>\n    - Host = evil.example:<port>\n3. In the request handler, inspect both:\n    - Request.getServerName(request)\n    - request.getHeaders().get(HttpHeader.HOST)\n4. Observe whether Jetty rejects the request or allows both values to remain visible.\nObserved result:\n    - HTTP/2: request is accepted and returns 200\n    - HTTP/3: request is accepted and returns 200\n    - the server can observe both:\n        - serverName=localhost\n        - hostHeader=evil.example:<port>\n\nThis shows that a single attacker-controlled request can preserve two conflicting host interpretations inside Jetty.\n\n#### Tests Used\n\n\nHTTP/2 rejection test:\n\n- `org.eclipse.jetty.http2.tests.HTTP2Test#testRejectMismatchedHostHeaderAndAuthority`\n\nHTTP/2 exploitability test:\n\n- `org.eclipse.jetty.http2.tests.HTTP2Test#testMismatchedHostHeaderAndAuthoritySplitsAuthorityFromHostHeader`\n\nHTTP/3 rejection test:\n\n- `org.eclipse.jetty.http3.tests.HandlerClientServerTest#testRejectMismatchedHostHeaderAndAuthority`\n\nHTTP/3 exploitability test:\n\n- `org.eclipse.jetty.http3.tests.HandlerClientServerTest#testMismatchedHostHeaderAndAuthoritySplitsAuthorityFromHostHeader`\n\n\nObserved behavior:\n\n- both rejection tests fail because Jetty returns 200 instead of 400\n- both exploitability tests pass, confirming that Jetty exposes different host values to different layers\n\n#### Project-Internal Evidence of Real Impact\n\nExamples:\n\n- `jetty-openid` uses `Request.getServerName(request)` to construct redirect URLs\n- `jetty-ee11-proxy` uses the raw `Host` header when building `Forwarded`\n\nThis indicates that the issue is not merely theoretical: Jetty’s own\necosystem already contains code paths where different host sources are\nused for different purposes.\n\n#### Affected Version\n\nConfirmed affected version:\n\n- 12.1.9-SNAPSHOT\n\nOther versions may also be affected if they share the same HTTP/2 /\nHTTP/3 request construction and compliance-validation logic. I have\nnot yet completed a historical version matrix and would recommend\nconfirming exact affected ranges from Jetty’s branch history.\n\n\n#### Suggested Fix\n\nRecommend adding HTTP/2 and HTTP/3 validation equivalent to the\nexisting HTTP/1.1 authority/Host consistency check:\n\n- if both :authority and regular Host are present\n    - normalize and compare them\n    - if they do not match, reject the request with 400 Bad Request\n    - route the failure through the existing MISMATCHED_AUTHORITY compliance mechanism\n\nAlso adding explicit HTTP/2 and HTTP/3 regression coverage for this case.\n\n#### Disclosure Status\n\n- not publicly disclosed\n- no public issue filed\n- shared only privately with the Jetty security contacts",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.eclipse.jetty:jetty-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "9.4.0.v20161208"
      }, {
        "last_affected" : "9.4.58.v20250814"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.eclipse.jetty:jetty-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "10.0.0"
      }, {
        "last_affected" : "10.0.26"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.eclipse.jetty:jetty-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "11.0.0"
      }, {
        "last_affected" : "11.0.26"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.eclipse.jetty:jetty-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "12.0.0"
      }, {
        "fixed" : "12.0.35"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 12.0.34"
    }
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.eclipse.jetty:jetty-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "12.1.0"
      }, {
        "fixed" : "12.1.9"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 12.1.8"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/jetty/jetty.project/security/advisories/GHSA-7p3p-8qv8-m2vh"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-6790"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/jetty/jetty.project/issues/14870"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/jetty/jetty.project/pull/14871"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/jetty/jetty.project/pull/14897"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/jetty/jetty.project/pull/14970"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/jetty/jetty.project/commit/3e5a4daec196859b8886b6f67b1157dab47cdb6f"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/jetty/jetty.project/commit/67ba9e6b39661810123680d9c894e99a7940c73d"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/jetty/jetty.project/commit/cbca3076f7c914a232e7a8b22fa95fbf7e67a6cc"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/jetty/jetty.project"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/jetty/jetty.project/releases/tag/jetty-12.0.35"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/jetty/jetty.project/releases/tag/jetty-12.1.9"
  }, {
    "type" : "WEB",
    "url" : "https://gitlab.eclipse.org/security/cve-assignment/-/work_items/99"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-20" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-07-22T22:56:43Z",
    "nvd_published_at" : "2026-07-14T09:16:41Z"
  }
}