diff --git a/README.md b/README.md
index 999240ed..f435d125 100644
--- a/README.md
+++ b/README.md
@@ -848,12 +848,17 @@ bash cms security blocklists
 
 Defaults: Spamhaus DROP/EDROP, DShield, CINS, Greensnow, StopForumSpam,
 Binary Defense, blocklist.de, Emerging Threats, BruteForceBlocker, abuse.ch
-Feodo/SSLBL/URLhaus, Botvrij, IPsum, Firehol ipsets and Tor exit nodes
-(26 sources). The largest commercial/crowdsourced lists (AbuseIPDB, MaxMind,
-Cisco Talos, AlienVault OTX) are not included because they require an account
-or API key; IPsum already aggregates ~30 additional feeds. No account is
-needed, but internet access is — only for fetching; detection and blocking
-remain local. Sync hourly as a cron job:
+Feodo/SSLBL, Botvrij, IPsum, Firehol ipsets and Tor exit nodes
+(25 sources). URLhaus was removed because its `text_online` feed lists URLs,
+not IPs; a malformed token in it could otherwise expand into a bogus
+huge CIDR. The validator only accepts whole-line bare IPs or proper CIDRs,
+enforces sane prefix bounds and drops reserved/private/loopback space, so a
+bad source entry can never block the origin or internal traffic. The largest
+commercial/crowdsourced lists (AbuseIPDB, MaxMind, Cisco Talos, AlienVault
+OTX) are not included because they require an account or API key; IPsum
+already aggregates ~30 additional feeds. No account is needed, but internet
+access is — only for fetching; detection and blocking remain local. Sync
+hourly as a cron job:
 
 ```bash
 bash cms security blocklists-install-cron
diff --git a/scripts/blocklists-sync.sh b/scripts/blocklists-sync.sh
index ae861780..32eaa3ff 100644
--- a/scripts/blocklists-sync.sh
+++ b/scripts/blocklists-sync.sh
@@ -26,7 +26,6 @@ DEFAULT_SOURCES=(
   # Malware C2 / botnets
   "https://feodotracker.abuse.ch/downloads/ipblocklist.txt"
   "https://sslbl.abuse.ch/blacklist/sslipblacklist.txt"
-  "https://urlhaus.abuse.ch/downloads/text_online/"
   "https://www.botvrij.eu/data/ioclist.ip-dst.raw"
   # Aggregated threat intel
   "https://raw.githubusercontent.com/stamparm/ipsum/master/levels/3.txt"
@@ -143,14 +142,59 @@ build_lists() {
   fetch_sources "$work"
 
   cat "$work"/source-*.txt 2>/dev/null | awk '{print $1}' \
-    | grep -Eo '([0-9]{1,3}\.){3}[0-9]{1,3}(/[0-9]+)?|([0-9a-fA-F]{1,4}:){2,}[0-9a-fA-F:]+(/[0-9]+)?' \
+    | grep -E '^([0-9]{1,3}\.){3}[0-9]{1,3}(/[0-9]{1,2})?$|^([0-9a-fA-F]{1,4}:){2,}[0-9a-fA-F:]*[0-9a-fA-F](/[0-9]{1,3})?$' \
     | awk '
+        # Only globally routable attacker space may become a decision. Reserved,
+        # private, loopback, link-local, CGNAT, test and multicast ranges never
+        # represent an external attacker and must not be imported (they could
+        # otherwise block the origin itself or internal traffic).
+        function isReserved4(prefix, a, b, c) {
+          if (a == 0 || a == 127 || a >= 224) return 1
+          if (a == 10) return 1
+          if (a == 100 && (prefix < 10 || (prefix >= 10 && b >= 64 && b <= 127))) return 1
+          if (a == 169 && (prefix < 16 || (prefix >= 16 && b == 254))) return 1
+          if (a == 172 && (prefix < 12 || (prefix >= 12 && b >= 16 && b <= 31))) return 1
+          if (a == 192 && b == 168) return 1
+          if (a == 192 && b == 0) return 1
+          if ((a == 198 && (b == 18 || b == 19)) || (a == 198 && b == 51 && c == 100)) return 1
+          if (a == 203 && b == 0 && c == 113) return 1
+          return 0
+        }
+        function isReserved6(line, prefix,   first, h) {
+          if (prefix < 32) return 1
+          if (line ~ /^::/) return 1
+          first = tolower(line); sub(/^::?/, "", first); sub(/:.*/, "", first)
+          h = "0x" substr(first, 1, 2)
+          if (h >= 252) return 1    # ULA fc00::/7, link-local fe80::/10, multicast ff00::/8
+          return 0
+        }
         {
           if (index($0, "/") > 0) {
             n = split($0, seg, "/")
             if (n != 2 || seg[2] !~ /^[0-9]+$/) next
-            if (index(seg[1], ":") > 0) { if (seg[2] + 0 <= 128) print; next }
-            if (seg[2] + 0 <= 32) print
+            if (index(seg[1], ":") > 0) {
+              pref = seg[2] + 0
+              if (pref < 32 || pref > 128) next
+              if (isReserved6(seg[1], pref)) next
+              print
+              next
+            }
+            pref = seg[2] + 0
+            if (pref < 8 || pref > 32) next
+            split(seg[1], oct, ".")
+            ok = 1
+            for (i = 1; i <= 4; i++) {
+              if (oct[i] !~ /^[0-9]+$/ || oct[i] + 0 > 255) { ok = 0; break }
+              if (length(oct[i]) > 1 && oct[i] ~ /^0/) { ok = 0; break }
+            }
+            if (!ok) next
+            if (isReserved4(pref, oct[1] + 0, oct[2] + 0, oct[3] + 0)) next
+            print
+            next
+          }
+          if (index($0, ":") > 0) {
+            if (isReserved6($0, 128)) next
+            print
             next
           }
           n = split($0, part, ".")
@@ -160,7 +204,9 @@ build_lists() {
             if (part[i] !~ /^[0-9]+$/ || part[i] + 0 > 255) { ok = 0; break }
             if (length(part[i]) > 1 && part[i] ~ /^0/) { ok = 0; break }
           }
-          if (ok) print
+          if (!ok) next
+          if (isReserved4(32, part[1] + 0, part[2] + 0, part[3] + 0)) next
+          print
         }' \
     | sort -u > "$work/candidates.txt"
 
diff --git a/src/lib/ddos-guard-crowdsec.test.ts b/src/lib/ddos-guard-crowdsec.test.ts
index dd8d814a..d7380f15 100644
--- a/src/lib/ddos-guard-crowdsec.test.ts
+++ b/src/lib/ddos-guard-crowdsec.test.ts
@@ -248,6 +248,15 @@ describe("anti-DDoS automatic CrowdSec blocks", () => {
 		expect(fetchMock).not.toHaveBeenCalled();
 	});
 
+	it("passes the unknown-IP sentinel through even when a stale block key exists", async () => {
+		state.map.set("antiddos:block:0.0.0.0", "1");
+
+		const decision = await enforceDdosRateLimit(directRequest("0.0.0.0"));
+
+		expect(decision.outcome).toBe("pass");
+		expect(fetchMock).not.toHaveBeenCalled();
+	});
+
 	it("blocks immediately on a local LAPI ban decision (app-layer bouncer)", async () => {
 		vi.stubEnv("CROWDSEC_LOCAL_ENABLED", "true");
 		vi.stubEnv("CROWDSEC_LAPI_URL", "http://127.0.0.1:18080");
diff --git a/src/lib/ddos-guard.ts b/src/lib/ddos-guard.ts
index 68796c8c..167e1e43 100644
--- a/src/lib/ddos-guard.ts
+++ b/src/lib/ddos-guard.ts
@@ -4,7 +4,7 @@ import type { NextRequest } from "next/server";
 import { NextResponse } from "next/server";
 import { env } from "@/env";
 import { getAntiddosConfig } from "@/lib/antiddos-config";
-import { resolveClientIp } from "@/lib/client-ip";
+import { resolveClientIp, UNKNOWN_CLIENT_IP } from "@/lib/client-ip";
 import { isCloudflareProxied } from "@/lib/cloudflare";
 import { maybeAutoBlockCloudflare } from "@/lib/cloudflare-api";
 import { maybeAutoBlockCrowdsec } from "@/lib/crowdsec-api";
@@ -71,6 +71,12 @@ export async function enforceDdosRateLimit(
 	}
 
 	const ip = resolveClientIp(req.headers);
+	// A trusted ingress always resolves a real client address. `0.0.0.0` is the
+	// sentinel for header-less loopback traffic (health checks, CI browser
+	// gates, monitoring). If it were rate-limited or blocked it would occupy a
+	// single shared key, and any burst of synthetic local traffic could then
+	// shed all origin-verified requests — exactly what broke CI smoke tests.
+	if (ip === UNKNOWN_CLIENT_IP) return { outcome: "pass" };
 	const blockKey = `antiddos:block:${ip}`;
 	if (redis) {
 		try {