diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 76e88cf7..bc6d0604 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -170,6 +170,18 @@ jobs:
           format: 'table'
           trivy-config: trivy.yaml
 
+      # Mirror of the release-time pre-publish smoke gate in docker-publish.yml.
+      # Catches the class of failure where the source-built Docker CLI or
+      # Compose plugin compiles cleanly but does not exec at runtime (e.g. -o
+      # pointed at a non-main Go package, ABI breakage in a base image bump).
+      # The release workflow additionally polls /api/health; PR CI keeps just
+      # the binary check to bound job duration without losing the gate.
+      - name: Smoke test built image (binaries)
+        run: |
+          set -euo pipefail
+          docker run --rm --entrypoint sh sencho:pr-test -c \
+            'docker --version && docker compose version'
+
   # ---------------------------------------------------------------------------
   # E2E Tests (PRs only, skipped for release-please PRs)
   # ---------------------------------------------------------------------------
diff --git a/.trivyignore b/.trivyignore
index 8c8cb747..ad13b99c 100644
--- a/.trivyignore
+++ b/.trivyignore
@@ -23,3 +23,14 @@
 # BSD operating systems and Sencho ships linux/amd64 + linux/arm64 only.
 # See security/vex/sencho.openvex.json for the full impact statement.
 CVE-2026-39883
+
+# Justification: covered by VEX statement for CVE-2026-34040 (Moby authz
+# bypass on oversized request body). compose v5.1.2 bundles the legacy
+# github.com/docker/docker@v28.5.2+incompatible as a client-side library
+# for API types and codecs; the daemon-side authz hook code path the CVE
+# affects is unreachable from a CLI client. The advisory's fix in
+# Docker Engine 29.3.1 ships under the new github.com/moby/moby/v2
+# module path which compose v5.1.2 does not yet import, so v28.5.2 is
+# the only Go-module-resolvable version reachable from compose. See
+# security/vex/sencho.openvex.json for the full impact statement.
+CVE-2026-34040
diff --git a/Dockerfile b/Dockerfile
index 46f92427..948b6929 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -144,12 +144,39 @@ WORKDIR /src/docker-compose
 
 RUN mkdir -p /build
 
+# Build target is ./cmd (the package main with plugin.Run), per docker/compose
+# v5.1.2's Makefile. The directory ./cmd/compose is package compose (cobra
+# command definitions only, not main). The module path moved from /v2 to /v5
+# in the v5 release, so the Version ldflag must reference /v5/internal.
+#
+# The bundled github.com/docker/docker dependency stays at v28.5.2+incompatible
+# (compose v5.1.2's go.mod). It cannot be upgraded to docker-v29.3.1 (the
+# release that contains the CVE-2026-34040 authz fix) because moby/moby's
+# docker-29.x branch declares its module path as github.com/moby/moby/v2,
+# making it unreachable through the legacy github.com/docker/docker import
+# that compose v5.1.2 still uses. The Go module proxy reflects this and lists
+# v28.5.2+incompatible as the highest resolvable version. The CVE only affects
+# Docker Engine's daemon authz hook code path; compose runs as a CLI client
+# and never executes that path. See security/vex/sencho.openvex.json for the
+# full not_affected justification, which Trivy honours via trivy.yaml.
 RUN --mount=type=cache,id=go-mod,sharing=locked,target=/go/pkg/mod \
     CGO_ENABLED=0 GOOS=linux GOARCH=${TARGETARCH} go build \
-      -ldflags "-extldflags=-static \
-        -X github.com/docker/compose/v2/internal.Version=v5.1.2" \
+      -trimpath \
+      -ldflags "-s -w -extldflags=-static \
+        -X github.com/docker/compose/v5/internal.Version=v5.1.2" \
       -o /build/docker-compose \
-      ./cmd/compose
+      ./cmd
+
+# Sanity check: fail the stage immediately if go build did not produce an ELF
+# executable. Catches the failure mode where -o file points to a non-main
+# package and Go writes an ar-format archive that passes COPY + chmod but is
+# not exec-able by the kernel, surfacing only as an opaque plugin-not-found
+# error from the Docker CLI plugin manager hundreds of build steps later.
+# `od -tx1` is used instead of `-c` because busybox and GNU coreutils render
+# `-c` with different field padding; hex output is stable across both.
+RUN test -f /build/docker-compose \
+ && magic=$(dd if=/build/docker-compose bs=1 count=4 status=none | od -An -tx1 | tr -d ' \n') \
+ && [ "$magic" = "7f454c46" ]
 
 # Stage 5: Production runtime
 # Runs on the TARGET platform - no compilation happens here.
diff --git a/security/vex/sencho.openvex.json b/security/vex/sencho.openvex.json
index 41cf1491..2c48dd6d 100644
--- a/security/vex/sencho.openvex.json
+++ b/security/vex/sencho.openvex.json
@@ -4,8 +4,8 @@
   "author": "Studio Saelix",
   "role": "Vendor",
   "timestamp": "2026-04-26T00:00:00Z",
-  "last_updated": "2026-04-26T00:00:00Z",
-  "version": 1,
+  "last_updated": "2026-04-27T00:00:00Z",
+  "version": 2,
   "statements": [
     {
       "vulnerability": {
@@ -18,7 +18,7 @@
           "@id": "pkg:oci/sencho",
           "subcomponents": [
             {
-              "@id": "pkg:golang/github.com/docker/docker@v28.5.2",
+              "@id": "pkg:golang/github.com/docker/docker@v28.5.2+incompatible",
               "location": "/usr/local/lib/docker/cli-plugins/docker-compose"
             }
           ]
@@ -26,7 +26,7 @@
       ],
       "status": "not_affected",
       "justification": "vulnerable_code_not_in_execute_path",
-      "impact_statement": "The authz bypass applies to Docker daemon plugin authorization hooks. docker-compose v5.1.2 statically bundles docker/docker v28.5.2 as a library but never acts as a daemon and never runs authorization hooks. Sencho invokes compose only for up/down/ps operations against local user-authored compose files. The daemon authz code path is not reachable."
+      "impact_statement": "The authz bypass affects Docker Engine's daemon-side plugin authorization hook on oversized request bodies. docker-compose v5.1.2 statically bundles docker/docker v28.5.2+incompatible as a client-side library for API types and codecs; it never acts as a daemon and never runs authorization hooks. Sencho invokes compose only for up/down/ps operations against local user-authored compose files. The daemon authz code path is not reachable. Note on remediation: the advisory's 'fixed in 29.3.1' refers to Docker Engine the daemon product. The Go library that contains the corresponding source fix is github.com/moby/moby/v2 (a new module path adopted on the docker-29.x branch), not github.com/docker/docker which compose v5.1.2 still imports. Until upstream compose migrates to the v2 import path the v28.5.2+incompatible bundled library is the only Go-module-resolvable version, and the not_affected status is the principled triage rather than a deferred upgrade."
     },
     {
       "vulnerability": {