diff --git a/.cargo/audit-expiries b/.cargo/audit-expiries
new file mode 100644
index 00000000..69db1638
--- /dev/null
+++ b/.cargo/audit-expiries
@@ -0,0 +1,3 @@
+# UTC expiry for each cargo-audit ignore. ci-preflight fails on this date.
+# .cargo/audit.toml cannot store the date; cargo-audit rejects unknown fields.
+RUSTSEC-2026-0258 2027-01-15
diff --git a/.cargo/audit.toml b/.cargo/audit.toml
new file mode 100644
index 00000000..65248594
--- /dev/null
+++ b/.cargo/audit.toml
@@ -0,0 +1,10 @@
+# RUSTSEC-2026-0258 (h2 0.3.27) has no fixed 0.3 release.
+# The libsql remote connector only offers HTTP/1.1 (src/remote_https.rs,
+# enforced by https_client_config_advertises_http11_alpn), so the h2 0.3
+# code path never runs. Upstream fix: tursodatabase/libsql#2224.
+# Tracked in #349. Expiry UTC date is in `.cargo/audit-expiries` (2027-01-15);
+# ci-preflight fails on that date until the exception is removed or re-reviewed.
+# Every ignored advisory needs an expiry line there; cargo-audit cannot store dates.
+
+[advisories]
+ignore = ["RUSTSEC-2026-0258"]
diff --git a/AGENTS.md b/AGENTS.md
index c4ebbb77..a7db5e86 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -249,8 +249,11 @@ workspace test runs only the in-process smoke), the API build without default fe
 and ordinary main pushes ignore reported CVE advisories but still fail when
 `cargo audit` cannot run). `npm audit --prefix tools/eslint --audit-level=high`
 always fails the `frontend` group on a high or critical advisory and on an
-advisory-endpoint failure. There is no fail-open switch and no ignore list;
-an unfixable transitive advisory is handled by pinning or dropping that package. GitHub-hosted Dependabot Updates dynamic workflows
+advisory-endpoint failure. There is no fail-open switch for cargo-audit; the only
+cargo-audit ignore is `RUSTSEC-2026-0258` in `.cargo/audit.toml` (see #349).
+Its UTC expiry is in `.cargo/audit-expiries` (2027-01-15); every ignored
+advisory needs an expiry line there. Any other unfixable transitive advisory is
+handled by pinning or dropping that package. GitHub-hosted Dependabot Updates dynamic workflows
 are not CI; do not add `.github/workflows` for them. Keep **Dependabot on self-hosted runners** disabled. This repository has no GitHub Actions self-hosted
 runners; otherwise jobs queue on a `dependabot` label and GitHub cancels
 them after 24 hours. Do not register leftover Proxmox GHA runners or label
diff --git a/Cargo.lock b/Cargo.lock
index 9e7d5708..1572385f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -322,9 +322,9 @@ checksum = "f079e83a288787bcd14a6aea84cee5c87a67c5a3e660c30f557a3d24761b3527"
 
 [[package]]
 name = "chacha20"
-version = "0.10.1"
+version = "0.10.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d524456ba66e72eb8b115ff89e01e497f8e6d11d78b70b1aa13c0fbd97540a81"
+checksum = "65c35e4b699c7e15ccbe7ee35c005e4fc0a278d22238a2857e6ce2dadeda1b06"
 dependencies = [
  "cfg-if",
  "cpufeatures 0.3.0",
@@ -2136,9 +2136,9 @@ dependencies = [
 
 [[package]]
 name = "rustls"
-version = "0.23.45"
+version = "0.23.46"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0d41d731c7d2f962d1ccc364cec258de3c0e93b38c2fb3ba97ac74513048d634"
+checksum = "48e13bd8c0e9365c43cfa5c9e8f9ad49d3c8444926c9aac819e0e4dc503c8fdf"
 dependencies = [
  "aws-lc-rs",
  "once_cell",
diff --git a/deny.toml b/deny.toml
index 292a46c4..ae93fb96 100644
--- a/deny.toml
+++ b/deny.toml
@@ -1,5 +1,6 @@
 # Supply-chain policy for cargo-deny (licenses, bans, sources).
-# Advisories are not part of this file. GitHub Actions runs cargo-audit:
+# Advisories are not part of this file; the single cargo-audit exception is
+# `.cargo/audit.toml`. GitHub Actions runs cargo-audit:
 # pull requests and ordinary main pushes do not fail the supply-chain check on a new
 # CVE advisories on the fail-open path; cargo-audit operational failures still fail the job.
 # Scheduled builds fail closed so the advisory is visible.
diff --git a/docs/CI.md b/docs/CI.md
index c45495e5..a2ad34ae 100644
--- a/docs/CI.md
+++ b/docs/CI.md
@@ -65,7 +65,12 @@ Both npm audits fail on high/critical findings or endpoint errors, including
 `npm audit --prefix tools/eslint --audit-level=high`. Cargo advisory reports remain
 non-blocking for PRs/ordinary main pushes; operational audit failures always fail.
 Scheduled runs set `JMODGUARD_AUDIT_FAIL_CLOSED=1`, run all gates, and withhold
-Nightly publication when an advisory is outstanding.
+Nightly publication when an advisory is outstanding. `RUSTSEC-2026-0258` is the
+one ignored cargo-audit advisory (see #349); its UTC expiry is in
+`.cargo/audit-expiries` (2027-01-15). Every ignored advisory needs an expiry
+there; any other unfixable advisory is handled by pinning or dropping that
+package. Preflight fails on the expiry date while the ignore remains. Scheduled
+runs still fail closed on every other advisory.
 
 ## Publication and trust
 
diff --git a/scripts/ci-preflight-test.sh b/scripts/ci-preflight-test.sh
index 1f7c661e..1f5908ac 100755
--- a/scripts/ci-preflight-test.sh
+++ b/scripts/ci-preflight-test.sh
@@ -170,3 +170,5 @@ if [ -f "$install_log" ]; then
 fi
 
 echo 'ci-preflight test: ensure_cargo_tool selection verified'
+
+bash "$root/scripts/ci-preflight.sh" --audit-expiry-self-check
diff --git a/scripts/ci-preflight.sh b/scripts/ci-preflight.sh
index 660cdda6..a8bc702f 100755
--- a/scripts/ci-preflight.sh
+++ b/scripts/ci-preflight.sh
@@ -4,6 +4,424 @@
 # Dependabot Updates dynamic workflows are not CI.
 set -euo pipefail
 
+# UTC calendar dates are YYYY-MM-DD. Expiry dates live in `.cargo/audit-expiries`.
+audit_ignore_is_expired() {
+  local today=$1 expiry=$2
+  (
+    LC_ALL=C
+    [[ "$today" == "$expiry" || "$today" > "$expiry" ]]
+  )
+}
+
+audit_date_is_ymd() {
+  local value=$1 normalized
+  [[ "$value" =~ ^[0-9]{4}-[0-9]{2}-[0-9]{2}$ ]] || return 1
+  normalized="$(TZ=UTC date -u -d "${value}T00:00:00Z" +%Y-%m-%d 2>/dev/null)" || return 1
+  [[ "$normalized" == "$value" ]]
+}
+
+audit_accept_today() {
+  local status=$1 raw=$2
+  [[ "$status" == 0 ]] || return 1
+  audit_date_is_ymd "$raw" || return 1
+  printf '%s\n' "$raw"
+  return 0
+}
+
+audit_read_expiries() {
+  local file=$1
+  local line id date seen=""
+  [[ -f "$file" ]] || return 1
+  while IFS= read -r line || [ -n "$line" ]; do
+    line="${line%%#*}"
+    line="${line#"${line%%[![:space:]]*}"}"
+    line="${line%"${line##*[![:space:]]}"}"
+    [ -n "$line" ] || continue
+    if [[ ! "$line" =~ ^([A-Z][A-Z0-9]*(-[0-9A-Z]+)+)[[:space:]]([0-9]{4}-[0-9]{2}-[0-9]{2})$ ]]; then
+      return 1
+    fi
+    id="${BASH_REMATCH[1]}"
+    date="${BASH_REMATCH[3]}"
+    audit_date_is_ymd "$date" || return 1
+    case " $seen " in
+      *" $id "*) return 1 ;;
+    esac
+    seen="${seen} ${id}"
+    printf '%s %s\n' "$id" "$date"
+  done <"$file"
+}
+
+audit_classify_report() {
+  local report=$1 ignores_out=$2
+  REPORT="$report" IGNORES_OUT="$ignores_out" node --input-type=commonjs - <<'JS'
+const fs = require("fs");
+
+const idRe = /^[A-Z][A-Z0-9]*(-[0-9A-Z]+)+$/;
+
+let report;
+try {
+  report = JSON.parse(fs.readFileSync(process.env.REPORT, "utf8"));
+} catch {
+  process.exit(1);
+}
+
+if (!report || Array.isArray(report) || typeof report !== "object") {
+  process.exit(1);
+}
+
+const vulnerabilities = report.vulnerabilities;
+if (
+  vulnerabilities == null ||
+  Array.isArray(vulnerabilities) ||
+  typeof vulnerabilities !== "object"
+) {
+  process.exit(1);
+}
+
+if (typeof vulnerabilities.found !== "boolean") {
+  process.exit(1);
+}
+
+const count = vulnerabilities.count;
+if (
+  !Number.isInteger(count) ||
+  count < 0
+) {
+  process.exit(1);
+}
+
+if (!Array.isArray(vulnerabilities.list)) {
+  process.exit(1);
+}
+
+for (const entry of vulnerabilities.list) {
+  const advId = entry.advisory?.id;
+  const pkg = entry.package;
+  if (!advId || !pkg?.name || !pkg?.version) {
+    process.exit(1);
+  }
+  console.error(`ci-preflight: advisory ${advId} ${pkg.name} ${pkg.version}`);
+}
+
+const ignoreSetting = report.settings?.ignore;
+const ignores = ignoreSetting == null ? [] : ignoreSetting;
+if (!Array.isArray(ignores)) {
+  process.exit(1);
+}
+
+const seen = new Set();
+for (const id of ignores) {
+  if (typeof id !== "string" || !idRe.test(id)) {
+    process.exit(1);
+  }
+  if (seen.has(id)) {
+    process.exit(1);
+  }
+  seen.add(id);
+}
+
+fs.writeFileSync(process.env.IGNORES_OUT, ignores.join("\n") + (ignores.length ? "\n" : ""), "utf8");
+
+const warnings = report.warnings || {};
+for (const kind of ["yanked", "unmaintained"]) {
+  for (const entry of warnings[kind] || []) {
+    const pkg = entry.package;
+    if (!pkg?.name || !pkg?.version) {
+      process.exit(1);
+    }
+    const adv = entry.advisory?.id;
+    if (adv) {
+      console.error(
+        `ci-preflight: warning ${kind} ${pkg.name} ${pkg.version} ${adv}`
+      );
+    } else {
+      console.error(
+        `ci-preflight: warning ${kind} ${pkg.name} ${pkg.version}`
+      );
+    }
+  }
+}
+
+if (!vulnerabilities.found && count === 0) {
+  process.stdout.write("-1");
+} else {
+  process.stdout.write(String(count));
+}
+JS
+}
+
+decide_audit_report() {
+  local report=$1 expiries=$2 audit_rc=$3 today_rc=$4 today_raw=$5 fail_closed=$6
+  local ignores_tmp expiries_tmp count classify_rc
+  local -A expiry_map=()
+  local id date line ignore_count=0 expiry_count=0 expired=0 restore_errexit=0
+  ignores_tmp="$(mktemp)"
+  expiries_tmp="$(mktemp)"
+  case "$-" in
+    *e*) restore_errexit=1 ;;
+  esac
+  set +e
+  dar_fin() {
+    if [ "$restore_errexit" -eq 1 ]; then
+      set -e
+    fi
+  }
+  count="$(audit_classify_report "$report" "$ignores_tmp")"
+  classify_rc=$?
+  if [ "$classify_rc" -ne 0 ]; then
+    rm -f "$ignores_tmp" "$expiries_tmp"
+    echo 'ci-preflight: cargo audit failed to run (operational error)' >&2
+    dar_fin
+    return 1
+  fi
+
+  # The parser prints valid lines before it returns 1. A process substitution
+  # would keep that prefix and hide the failure, so keep the exit status.
+  if ! audit_read_expiries "$expiries" >"$expiries_tmp"; then
+    rm -f "$ignores_tmp" "$expiries_tmp"
+    echo 'ci-preflight: cargo audit expiry file is invalid' >&2
+    dar_fin
+    return 1
+  fi
+  while IFS= read -r line || [ -n "$line" ]; do
+    [ -n "$line" ] || continue
+    id="${line%% *}"
+    date="${line#* }"
+    expiry_map["$id"]="$date"
+    expiry_count=$((expiry_count + 1))
+  done <"$expiries_tmp"
+  rm -f "$expiries_tmp"
+
+  while IFS= read -r id || [ -n "$id" ]; do
+    [ -n "$id" ] || continue
+    ignore_count=$((ignore_count + 1))
+    date="${expiry_map[$id]:-}"
+    if [ -z "$date" ]; then
+      rm -f "$ignores_tmp"
+      echo "ci-preflight: cargo audit ignore ${id} has no expiry in .cargo/audit-expiries" >&2
+      dar_fin
+      return 1
+    fi
+  done <"$ignores_tmp"
+
+  for id in "${!expiry_map[@]}"; do
+    if ! grep -Fxq "$id" "$ignores_tmp" 2>/dev/null; then
+      rm -f "$ignores_tmp"
+      echo "ci-preflight: cargo audit expiry ${id} is not ignored" >&2
+      dar_fin
+      return 1
+    fi
+  done
+
+  if [ "$ignore_count" -gt 0 ] || [ "$expiry_count" -gt 0 ]; then
+    if [ "$today_rc" -ne 0 ] || ! audit_date_is_ymd "$today_raw"; then
+      rm -f "$ignores_tmp"
+      echo 'ci-preflight: cargo audit exception expiry date is unavailable' >&2
+      dar_fin
+      return 1
+    fi
+    while IFS= read -r id || [ -n "$id" ]; do
+      [ -n "$id" ] || continue
+      date="${expiry_map[$id]}"
+      if [ "$id" = RUSTSEC-2026-0258 ]; then
+        echo "ci-preflight: advisory ${id} ignored (expires ${date}; see #349)" >&2
+        if audit_ignore_is_expired "$today_raw" "$date"; then
+          echo "ci-preflight: cargo audit exception ${id} expired on ${date}; see #349; re-review the exception" >&2
+          expired=1
+        fi
+      else
+        echo "ci-preflight: advisory ${id} ignored (expires ${date})" >&2
+        if audit_ignore_is_expired "$today_raw" "$date"; then
+          echo "ci-preflight: cargo audit exception ${id} expired on ${date}; re-review the exception" >&2
+          expired=1
+        fi
+      fi
+    done <"$ignores_tmp"
+    if [ "$expired" -eq 1 ]; then
+      rm -f "$ignores_tmp"
+      dar_fin
+      return 1
+    fi
+  fi
+
+  rm -f "$ignores_tmp"
+
+  if [ "$count" = -1 ]; then
+    if [ "$audit_rc" -eq 0 ]; then
+      dar_fin
+      return 0
+    fi
+    echo 'ci-preflight: cargo audit failed to run (unexpected exit 1 without advisories)' >&2
+    dar_fin
+    return 1
+  fi
+
+  if [ "$fail_closed" = 1 ]; then
+    echo "ci-preflight: cargo audit failed closed (scheduled CI; ${count} advisories)" >&2
+    dar_fin
+    return 1
+  fi
+
+  echo "ci-preflight: cargo audit reported ${count} advisories; pull requests and ordinary main pushes do not fail the supply-chain check" >&2
+  dar_fin
+  return 0
+}
+
+if [ "${1:-}" = "--audit-expiry-self-check" ]; then
+  fail() { echo "ci-preflight: audit expiry self-check: $*" >&2; exit 1; }
+  self_root="$(cd "$(dirname "$0")/.." && pwd)"
+  real_expiries="${self_root}/.cargo/audit-expiries"
+
+  audit_ignore_is_expired 2024-05-01 2024-05-02 && fail "2024-05-01 must stay valid before 2024-05-02"
+  audit_ignore_is_expired 2024-05-02 2024-05-02 || fail "2024-05-02 must expire on 2024-05-02"
+  audit_ignore_is_expired 2024-05-03 2024-05-02 || fail "2024-05-03 must expire after 2024-05-02"
+
+  audit_accept_today 1 2024-05-02 >/dev/null 2>&1 && fail "audit_accept_today must fail for status 1"
+  audit_accept_today 0 not-a-date >/dev/null 2>&1 && fail "audit_accept_today must fail for not-a-date"
+  audit_accept_today 0 2027-13-40 >/dev/null 2>&1 && fail "audit_accept_today must fail for 2027-13-40"
+  out="$(audit_accept_today 0 2024-05-02)" || fail "audit_accept_today must accept 2024-05-02"
+  [ "$out" = 2024-05-02 ] || fail "audit_accept_today must echo 2024-05-02"
+
+  tmp="$(mktemp -d)"
+  trap 'rm -rf "$tmp"' EXIT
+
+  write_report() {
+    printf '%s' "$1" >"$tmp/report.json"
+  }
+
+  decide_expect() {
+    local expect_rc=$1
+    local report_json=$2 expiries_file=$3 audit_rc=$4 today_rc=$5 today_raw=$6 fail_closed=$7
+    local rc
+    write_report "$report_json"
+    : >"$tmp/decide.err"
+    set +e
+    decide_audit_report "$tmp/report.json" "$expiries_file" "$audit_rc" "$today_rc" "$today_raw" "$fail_closed" 2>"$tmp/decide.err"
+    rc=$?
+    set -e
+    if [ "$rc" -ne "$expect_rc" ]; then
+      cat "$tmp/decide.err" >&2
+      fail "decide_audit_report expected rc ${expect_rc}, got ${rc}"
+    fi
+  }
+
+  printf '\n' >"$tmp/empty-expiries"
+
+  decide_expect 1 '{' "$tmp/empty-expiries" 0 0 2024-05-02 0
+  grep -Fq 'operational error' "$tmp/decide.err" || fail 'malformed JSON must print operational error'
+
+  decide_expect 1 '{}' "$tmp/empty-expiries" 0 0 2024-05-02 0
+  grep -Fq 'operational error' "$tmp/decide.err" || fail 'missing vulnerabilities must print operational error'
+
+  decide_expect 1 '{"vulnerabilities":null}' "$tmp/empty-expiries" 0 0 2024-05-02 0
+  grep -Fq 'operational error' "$tmp/decide.err" || fail 'null vulnerabilities must print operational error'
+
+  decide_expect 1 '{"vulnerabilities":[]}' "$tmp/empty-expiries" 0 0 2024-05-02 0
+  grep -Fq 'operational error' "$tmp/decide.err" || fail 'array vulnerabilities must print operational error'
+
+  decide_expect 0 '{"vulnerabilities":{"found":false,"count":0,"list":[]}}' "$tmp/empty-expiries" 0 0 2024-05-02 0
+  decide_expect 0 '{"vulnerabilities":{"found":false,"count":0,"list":[]}}' "$tmp/empty-expiries" 0 0 2024-05-02 1
+
+  one_adv='{"vulnerabilities":{"found":true,"count":1,"list":[{"advisory":{"id":"RUSTSEC-2020-0001"},"package":{"name":"crate","version":"1.0.0"}}]},"settings":{"ignore":[]}}'
+  decide_expect 0 "$one_adv" "$tmp/empty-expiries" 0 0 2024-05-02 0
+  grep -Fq 'pull requests and ordinary main pushes do not fail' "$tmp/decide.err" || fail 'one advisory fail-open must print PR sentence'
+  decide_expect 1 "$one_adv" "$tmp/empty-expiries" 0 0 2024-05-02 1
+  grep -Fq 'failed closed' "$tmp/decide.err" || fail 'one advisory fail-closed must print failed closed'
+
+  decide_expect 1 '{"vulnerabilities":{"found":false,"count":0,"list":[]}}' "$tmp/empty-expiries" 1 0 2024-05-02 0
+  grep -Fq 'unexpected exit 1 without advisories' "$tmp/decide.err" || fail 'exit 1 empty report must print unexpected exit 1'
+
+  printf 'RUSTSEC-2026-0001 2099-01-01\n' >"$tmp/partial-expiries"
+  two_ignore='{"vulnerabilities":{"found":false,"count":0,"list":[]},"settings":{"ignore":["RUSTSEC-2026-0001","RUSTSEC-2026-0002"]}}'
+  decide_expect 1 "$two_ignore" "$tmp/partial-expiries" 0 0 2024-05-02 0
+  grep -Fq 'RUSTSEC-2026-0002' "$tmp/decide.err" || fail 'missing expiry must name RUSTSEC-2026-0002'
+  grep -Fq 'has no expiry' "$tmp/decide.err" || fail 'missing expiry must print has no expiry'
+
+  printf 'RUSTSEC-2026-9999 2099-01-01\n' >"$tmp/orphan-expiry"
+  no_ignore='{"vulnerabilities":{"found":false,"count":0,"list":[]},"settings":{"ignore":[]}}'
+  decide_expect 1 "$no_ignore" "$tmp/orphan-expiry" 0 0 2024-05-02 0
+  grep -Fq 'is not ignored' "$tmp/decide.err" || fail 'orphan expiry must print is not ignored'
+
+  printf 'RUSTSEC-2026-0001 2099-06-01\nRUSTSEC-2026-0002 2099-12-01\n' >"$tmp/two-future"
+  two_ignore_ok='{"vulnerabilities":{"found":false,"count":0,"list":[]},"settings":{"ignore":["RUSTSEC-2026-0001","RUSTSEC-2026-0002"]}}'
+  decide_expect 0 "$two_ignore_ok" "$tmp/two-future" 0 0 2024-05-02 0
+  grep -Fq 'RUSTSEC-2026-0001 ignored (expires 2099-06-01)' "$tmp/decide.err" || fail 'two future: first ignore line'
+  grep -Fq 'RUSTSEC-2026-0002 ignored (expires 2099-12-01)' "$tmp/decide.err" || fail 'two future: second ignore line'
+
+  printf 'RUSTSEC-2026-0001 2024-05-01\nRUSTSEC-2026-0002 2099-12-01\n' >"$tmp/today-expire"
+  decide_expect 1 "$two_ignore_ok" "$tmp/today-expire" 0 0 2024-05-01 0
+  grep -Fq 'expired on' "$tmp/decide.err" || fail 'today equal earlier expiry must print expired on'
+  grep -Fq 'RUSTSEC-2026-0001' "$tmp/decide.err" || fail 'today equal earlier expiry must name id'
+  grep -Fq '2024-05-01' "$tmp/decide.err" || fail 'today equal earlier expiry must name date'
+
+  printf 'RUSTSEC-2026-0001 2024-05-01\nRUSTSEC-2026-0002 2024-05-02\n' >"$tmp/both-expired"
+  decide_expect 1 "$two_ignore_ok" "$tmp/both-expired" 0 0 2024-05-02 0
+  grep -Fq 'exception RUSTSEC-2026-0001 expired on 2024-05-01' "$tmp/decide.err" || fail 'both expired must name the first id'
+  grep -Fq 'exception RUSTSEC-2026-0002 expired on 2024-05-02' "$tmp/decide.err" || fail 'both expired must name the second id'
+
+  # Pullfrog repro: a valid prefix must not survive a later parser failure.
+  rustsec_only='{"vulnerabilities":{"found":false,"count":0,"list":[]},"settings":{"ignore":["RUSTSEC-2026-0258"]}}'
+  printf '%s\n' 'RUSTSEC-2026-0258 2027-01-15' 'RUSTSEC-2026-0258 2026-01-15' >"$tmp/dup-expiries"
+  decide_expect 1 "$rustsec_only" "$tmp/dup-expiries" 0 0 2026-10-17 0
+  grep -Fq 'expiry file is invalid' "$tmp/decide.err" || fail 'duplicate expiry id must print expiry file is invalid when fail-open'
+  decide_expect 1 "$rustsec_only" "$tmp/dup-expiries" 0 0 2026-10-17 1
+  grep -Fq 'expiry file is invalid' "$tmp/decide.err" || fail 'duplicate expiry id must print expiry file is invalid when fail-closed'
+  printf '%s\n' 'RUSTSEC-2026-0258 2027-01-15' 'INVALID-LINE' >"$tmp/malformed-expiries"
+  decide_expect 1 "$rustsec_only" "$tmp/malformed-expiries" 0 0 2026-10-17 0
+  grep -Fq 'expiry file is invalid' "$tmp/decide.err" || fail 'malformed expiry line must print expiry file is invalid when fail-open'
+  decide_expect 1 "$rustsec_only" "$tmp/malformed-expiries" 0 0 2026-10-17 1
+  grep -Fq 'expiry file is invalid' "$tmp/decide.err" || fail 'malformed expiry line must print expiry file is invalid when fail-closed'
+  printf '%s\n' 'RUSTSEC-2026-0258 2027-01-15' 'RUSTSEC-2026-0002 2026-13-40' >"$tmp/bad-date-expiries"
+  decide_expect 1 "$rustsec_only" "$tmp/bad-date-expiries" 0 0 2026-10-17 0
+  grep -Fq 'expiry file is invalid' "$tmp/decide.err" || fail 'invalid expiry date must print expiry file is invalid when fail-open'
+  decide_expect 1 "$rustsec_only" "$tmp/bad-date-expiries" 0 0 2026-10-17 1
+  grep -Fq 'expiry file is invalid' "$tmp/decide.err" || fail 'invalid expiry date must print expiry file is invalid when fail-closed'
+
+  printf 'RUSTSEC-2026-0001 2099-01-01\n' >"$tmp/one-future"
+  one_ignore='{"vulnerabilities":{"found":false,"count":0,"list":[]},"settings":{"ignore":["RUSTSEC-2026-0001"]}}'
+  decide_expect 1 "$one_ignore" "$tmp/one-future" 0 1 '' 0
+  grep -Fq 'expiry date is unavailable' "$tmp/decide.err" || fail 'today_rc 1 must print expiry date is unavailable'
+  decide_expect 1 "$one_ignore" "$tmp/one-future" 0 0 'yesterday' 0
+  grep -Fq 'expiry date is unavailable' "$tmp/decide.err" || fail 'non-calendar today must print expiry date is unavailable'
+
+  decide_expect 0 '{"vulnerabilities":{"found":false,"count":0,"list":[]}}' "$tmp/empty-expiries" 0 1 '' 0
+
+  rustsec_expiry="$(awk '/^RUSTSEC-2026-0258 / {print $2; exit}' "$real_expiries")"
+  [ -n "$rustsec_expiry" ] || fail 'real audit-expiries must list RUSTSEC-2026-0258'
+  data_lines="$(grep -cE '^RUSTSEC-' "$real_expiries" || true)"
+  [ "$data_lines" = 1 ] || fail 'audit-expiries must contain exactly one advisory line'
+  grep -F "$rustsec_expiry" "$self_root/AGENTS.md" >/dev/null || fail 'AGENTS.md must document the enforced expiry'
+  grep -F "$rustsec_expiry" "$self_root/docs/CI.md" >/dev/null || fail 'docs/CI.md must document the enforced expiry'
+  grep -F "$rustsec_expiry" "$self_root/.cargo/audit.toml" >/dev/null || fail 'audit.toml must document the enforced expiry'
+  day_before="$(TZ=UTC date -u -d "${rustsec_expiry}T00:00:00Z - 1 day" +%Y-%m-%d)"
+  rustsec_ok='{"vulnerabilities":{"found":false,"count":0,"list":[]},"settings":{"ignore":["RUSTSEC-2026-0258"]}}'
+  decide_expect 0 "$rustsec_ok" "$real_expiries" 0 0 "$day_before" 0
+  grep -Fq "ignored (expires ${rustsec_expiry}; see #349)" "$tmp/decide.err" || fail 'documented date: day before must print ignored with see #349'
+  decide_expect 1 "$rustsec_ok" "$real_expiries" 0 0 "$rustsec_expiry" 0
+  grep -Fq "expired on ${rustsec_expiry}; see #349; re-review the exception" "$tmp/decide.err" || fail 'documented date: expiry day must print expired with see #349'
+
+  write_report '{"vulnerabilities":{"found":false,"count":0,"list":[]}}'
+  set -e
+  decide_audit_report "$tmp/report.json" "$tmp/empty-expiries" 0 0 2024-05-02 0
+  case $- in
+    *e*) ;;
+    *) fail 'decide_audit_report disabled errexit on success' ;;
+  esac
+  set +e
+  decide_audit_report "$tmp/report.json" "$tmp/missing-expiries" 0 0 2024-05-02 0 2>"$tmp/decide.err"
+  errexit_rc=$?
+  set -e
+  [ "$errexit_rc" -ne 0 ] || fail 'missing expiry file must fail'
+  grep -Fq 'expiry file is invalid' "$tmp/decide.err" || fail 'missing expiry file must print expiry file is invalid'
+  case $- in
+    *e*) ;;
+    *) fail 'decide_audit_report left errexit disabled after failure' ;;
+  esac
+
+  echo "ci-preflight: audit expiry self-check passed"
+  exit 0
+fi
+
 root="$(git rev-parse --show-toplevel)"
 cd "$root"
 
@@ -259,7 +677,7 @@ EOF
 # failures (for example advisory DB fetch/load). Classify from JSON stdout and
 # stderr instead of trusting exit 1 alone.
 run_cargo_audit_gate() {
-  local audit_out audit_err audit_rc advisory_count
+  local audit_out audit_err audit_rc today_raw today_rc fail_closed decide_rc
   audit_out="$(mktemp)"
   audit_err="$(mktemp)"
   set +e
@@ -270,61 +688,43 @@ run_cargo_audit_gate() {
     cat "$audit_err" >&2
   fi
 
-  if [ "$audit_rc" -eq 0 ]; then
-    rm -f "$audit_out" "$audit_err"
-    return 0
-  fi
-
   if [ "$audit_rc" -eq 2 ]; then
     echo "ci-preflight: cargo audit failed to run (exit ${audit_rc})" >&2
     rm -f "$audit_out" "$audit_err"
     return 1
   fi
 
-  if [ "$audit_rc" -ne 1 ]; then
+  if [ "$audit_rc" -ne 0 ] && [ "$audit_rc" -ne 1 ]; then
     echo "ci-preflight: cargo audit failed to run (exit ${audit_rc})" >&2
     rm -f "$audit_out" "$audit_err"
     return 1
   fi
 
-  if grep -qE '^error:' "$audit_err" || [ ! -s "$audit_out" ]; then
-    echo 'ci-preflight: cargo audit failed to run (operational error)' >&2
-    rm -f "$audit_out" "$audit_err"
-    return 1
+  if [ "$audit_rc" -eq 1 ]; then
+    if grep -qE '^error:' "$audit_err" || [ ! -s "$audit_out" ]; then
+      echo 'ci-preflight: cargo audit failed to run (operational error)' >&2
+      rm -f "$audit_out" "$audit_err"
+      return 1
+    fi
   fi
 
-  advisory_count="$(
-    AUDIT_OUT="$audit_out" node --input-type=commonjs - <<'JS'
-const fs = require("fs");
-const report = JSON.parse(fs.readFileSync(process.env.AUDIT_OUT, "utf8"));
-const vulnerabilities = report.vulnerabilities || {};
-let count = vulnerabilities.count;
-if (count == null) {
-  count = (vulnerabilities.list || []).length;
-}
-if (vulnerabilities.found || count) {
-  process.stdout.write(String(Number(count)));
-} else {
-  process.stdout.write("-1");
-}
-JS
-  )" || advisory_count=-1
-
-  if [ "$advisory_count" -lt 0 ]; then
-    echo 'ci-preflight: cargo audit failed to run (unexpected exit 1 without advisories)' >&2
-    rm -f "$audit_out" "$audit_err"
-    return 1
+  today_raw=""
+  today_rc=1
+  if today_raw="$(date -u +%Y-%m-%d 2>/dev/null)"; then
+    today_rc=0
   fi
 
-  if [ "${JMODGUARD_AUDIT_FAIL_CLOSED:-0}" = "1" ]; then
-    echo "ci-preflight: cargo audit failed closed (scheduled CI; ${advisory_count} advisories)" >&2
-    rm -f "$audit_out" "$audit_err"
-    return 1
+  fail_closed=0
+  if [ "${JMODGUARD_AUDIT_FAIL_CLOSED:-}" = "1" ]; then
+    fail_closed=1
   fi
 
-  echo "ci-preflight: cargo audit reported ${advisory_count} advisories; pull requests and ordinary main pushes do not fail the supply-chain check" >&2
+  set +e
+  decide_audit_report "$audit_out" "$root/.cargo/audit-expiries" "$audit_rc" "$today_rc" "$today_raw" "$fail_closed"
+  decide_rc=$?
+  set -e
   rm -f "$audit_out" "$audit_err"
-  return 0
+  return "$decide_rc"
 }
 
 whitespace_check() {