CVE-2026-10051

In Eclipse Jetty, a first HTTP/1.1 request with trailers causes the server to retain the trailers in subsequent requests performed over the same connection. Subsequent request that do not have trailers report the trailers of the first request. Subsequent request that do have trailers report the union of trailers of the first request and the current request.

In Eclipse Jetty, a first HTTP/1.1 request with trailers causes the server to retain the trailers in subsequent requests performed over the same connection. Subsequent request that do not have trailers report the trailers of the first request. Subsequent request that do have trailers report the union of trailers of the first request and the current request.

Description

FINDING — MEDIUM (HTTP/1.1 keep-alive connections with trailers) HttpConnection._trailers Cross-Request Leakage (Never Reset Between Requests)

Location: jetty-core/jetty-server/src/main/java/org/eclipse/jetty/server/internal/ HttpConnection.java:107, 1157-1161, 1170

Detail: _trailers (line 107) is a connection-scoped HttpFields.Mutable field. parsedTrailer() (line 1157) populates it when request N carries HTTP trailers. messageComplete() (line 1170) checks "if (_trailers != null)" — evaluates true from request N's data — and stamps it onto request N+1.

Grep confirms: ZERO occurrences of "_trailers = null" in entire HttpConnection.java.

Scenario: Request N: POST /upload (trailers: X-Checksum: abc123) Request N+1: GET /data (no trailers) app: request.getTrailers() on N+1 → returns {X-Checksum: abc123} ← STALE

Application logic branching on getTrailers() != null produces incorrect behavior. Not cross-connection (same keep-alive connection only).

More dangerous scenario: TOCTOU — trailer passes check, target swapped before use.

Workarounds

Do not rely on HTTP request trailers for security-sensitive logic, or disable persistent connections by closing the connection after each HTTP/1.1 request.

In Eclipse Jetty, a first HTTP/1.1 request with trailers causes the server to retain the trailers in subsequent requests performed over the same connection. Subsequent request that do not have trailers report the trailers of the first request. Subsequent request that do have trailers report the union of trailers of the first request and the current request.

In Eclipse Jetty, a first HTTP/1.1 request with trailers causes the server to retain the trailers in subsequent requests performed over the same connection. Subsequent request that do not have trailers report the trailers of the first request. Subsequent request that do have trailers report the union of trailers of the first request and the current request.

In Eclipse Jetty, a first HTTP/1.1 request with trailers causes the server to retain the trailers in subsequent requests performed over the same connection. Subsequent request that do not have trailers report the trailers of the first request. Subsequent request that do have trailers report the union of trailers of the first request and the current request.