{"id":"CVE-2026-73494","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-73494","summary":"blaze: Multiple HTTP/1.1 request-smuggling primitives in blaze's Java wire parser","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.","published":"2026-07-24T22:26:27Z","modified":"2026-08-12T21:15:09.447475769Z","cvss":{"score":7.4,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Maven","name":"org.http4s:http4s-blaze-server_2.13","fixedVersion":"0.23.18"},{"ecosystem":"Maven","name":"org.http4s:blaze-http_2.13","fixedVersion":"0.23.18"},{"ecosystem":"Maven","name":"org.http4s:blaze-http_3","fixedVersion":"0.23.18"},{"ecosystem":"Maven","name":"org.http4s:blaze-http_3","fixedVersion":"1.0.0-M42"},{"ecosystem":"Maven","name":"org.http4s:blaze-http_2.13","fixedVersion":"1.0.0-M42"}],"fix":{"url":"https://github.com/http4s/blaze/commit/3f7c022e306631b006dcb43a1d7f65c0d1966f17","label":"http4s/blaze@3f7c022"},"references":[{"type":"WEB","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":"PACKAGE","url":"https://github.com/http4s/blaze"},{"type":"WEB","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"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T21:15:09.447475769Z"}}