{
"id": "GHSA-mhvj-jhpq-885v",
"aliases": [
"CVE-2026-73494"
],
"details": "### Summary\n Five independent HTTP/1.1 conformance laxities in blaze's hand-written Java parser (`http/src/main/java/org/http4s/blaze/http/parser/`) cause request-boundary disagreement with a stricter intermediary. All are reachable from a default `BlazeServerBuilder` with no non-default configuration.\n\n### Impact\nActual exploitability depends on the fronting proxy — a boundary disagreement requires a *pair* of parsers that disagree. Where the proxy forwards the malformed bytes and derives a different message boundary, the consequences are the standard set: front-end ACL/auth bypass, response-queue poisoning on pooled backend connections, and cache poisoning. Risk concentrates on lenient or legacy intermediaries.\n\n### Workarounds\n Deploy behind an RFC-strict reverse proxy (nginx, HAProxy, Envoy, ALB) that rejects or re-serializes malformed requests at the edge; this neutralizes most of these for deployments that cannot upgrade immediately.",
"summary": "blaze: Multiple HTTP/1.1 request-smuggling primitives in blaze's Java wire parser",
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.23.18"
}
]
}
],
"package": {
"name": "org.http4s:http4s-blaze-server_2.13",
"ecosystem": "Maven"
},
"database_specific": {
"last_known_affected_version_range": "<= 0.23.17"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.23.18"
}
]
}
],
"package": {
"name": "org.http4s:blaze-http_2.13",
"ecosystem": "Maven"
},
"database_specific": {
"last_known_affected_version_range": "<= 0.23.17"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.23.18"
}
]
}
],
"package": {
"name": "org.http4s:blaze-http_3",
"ecosystem": "Maven"
},
"database_specific": {
"last_known_affected_version_range": "<= 0.23.17"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "1.0.0-M1"
},
{
"fixed": "1.0.0-M42"
}
]
}
],
"package": {
"name": "org.http4s:blaze-http_3",
"ecosystem": "Maven"
},
"database_specific": {
"last_known_affected_version_range": "<= 1.0.0-M41"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "1.0.0-M1"
},
{
"fixed": "1.0.0-M42"
}
]
}
],
"package": {
"name": "org.http4s:blaze-http_2.13",
"ecosystem": "Maven"
},
"database_specific": {
"last_known_affected_version_range": "<= 1.0.0-M41"
}
}
],
"modified": "2026-08-12T21:12:10Z",
"severity": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"
}
],
"published": "2026-07-24T22:26:27Z",
"references": [
{
"url": "https://github.com/http4s/blaze/security/advisories/GHSA-mhvj-jhpq-885v",
"type": "WEB"
},
{
"url": "https://github.com/http4s/blaze/commit/3f7c022e306631b006dcb43a1d7f65c0d1966f17",
"type": "WEB"
},
{
"url": "https://github.com/http4s/blaze/commit/4eec2007806aa9acfefb00ebb636ddc39a147a96",
"type": "WEB"
},
{
"url": "https://github.com/http4s/blaze/commit/927b67753a78c13c4445dac9307f511f5c4878c3",
"type": "WEB"
},
{
"url": "https://github.com/http4s/blaze/commit/a54bc9cd31758335c7f24e29763622fd03fcf734",
"type": "WEB"
},
{
"url": "https://github.com/http4s/blaze/commit/c47d9675f87603f11b32a11d503626bdf9be5c7a",
"type": "WEB"
},
{
"url": "https://github.com/http4s/blaze/commit/e871ebb1d27f50c98fd56988526ce42d0fee74d6",
"type": "WEB"
},
{
"url": "https://github.com/http4s/blaze",
"type": "PACKAGE"
},
{
"url": "https://github.com/http4s/blaze/releases/tag/v0.23.18",
"type": "WEB"
},
{
"url": "https://github.com/http4s/blaze/releases/tag/v1.0.0-M42",
"type": "WEB"
}
],
"schema_version": "1.4.0",
"database_specific": {
"cwe_ids": [
"CWE-444"
],
"severity": "HIGH",
"github_reviewed": true,
"nvd_published_at": null,
"github_reviewed_at": "2026-07-24T22:26:27Z"
}
}