diff --git a/src/hooks/useBondManagement.ts b/src/hooks/useBondManagement.ts
index 3f35219..c46b482 100644
--- a/src/hooks/useBondManagement.ts
+++ b/src/hooks/useBondManagement.ts
@@ -1,6 +1,7 @@
 import { useCallback, useMemo, useRef, useState } from "react";
 import useSWR from "swr";
 import { walletAdapter } from "@/lib/wallet";
+import { checkOriginTrusted } from "@/lib/wallet/assertWalletReady";
 import { decodeXdr, XdrMismatchError } from "@/lib/xdrReview";
 import { getBondAdapter } from "@/lib/bond/adapter";
 import { applyBondOperation } from "@/lib/bond/state";
@@ -49,6 +50,7 @@ export function useBondManagement(address: string | null, adapter: BondAdapter =
             throw new XdrMismatchError("Bond transaction contains no operations — refusing to sign.");
           }
           setStatus("awaiting-signature");
+          checkOriginTrusted();
           signedXdr = await walletAdapter.signTransaction(unsignedXdr, { network: wallet.network ?? undefined });
         }
 
diff --git a/src/hooks/useSolverRegistration.test.ts b/src/hooks/useSolverRegistration.test.ts
index 72451cc..840c169 100644
--- a/src/hooks/useSolverRegistration.test.ts
+++ b/src/hooks/useSolverRegistration.test.ts
@@ -64,6 +64,7 @@ vi.mock("@/lib/xdrReview", () => {
 });
 
 vi.mock("@/lib/wallet/assertWalletReady", () => ({
+  checkOriginTrusted: vi.fn(),
   assertWalletReady: assertWalletReadyMock,
   UntrustedOriginError: class UntrustedOriginError extends Error {
     constructor(hostname: string) {
diff --git a/src/hooks/useSolverRegistration.ts b/src/hooks/useSolverRegistration.ts
index e02888d..bc49f73 100644
--- a/src/hooks/useSolverRegistration.ts
+++ b/src/hooks/useSolverRegistration.ts
@@ -1,7 +1,7 @@
 import { useCallback, useRef, useState } from "react";
 import { mutate } from "swr";
 import { walletAdapter } from "@/lib/wallet";
-import { assertWalletReady } from "@/lib/wallet/assertWalletReady";
+import { assertWalletReady, checkOriginTrusted } from "@/lib/wallet/assertWalletReady";
 import { registerSolver, submitSolverRegistration } from "@/lib/api";
 import { ApiError } from "@/lib/api";
 import { verifySignedXdrMatches } from "@/lib/xdrReview";
@@ -91,6 +91,7 @@ export function useSolverRegistration() {
       // Origin-trust guard: refuse to sign on untrusted origins.
       assertWalletReady();
 
+      checkOriginTrusted();
       const signedXdr = await walletAdapter.signTransaction(unsignedXdr, {
         network: wallet.network ?? undefined,
       });
diff --git a/src/lib/export/analyticsExport.ts b/src/lib/export/analyticsExport.ts
index 37a09a1..25a4b3c 100644
--- a/src/lib/export/analyticsExport.ts
+++ b/src/lib/export/analyticsExport.ts
@@ -5,6 +5,8 @@
  */
 
 import { escapeCsv } from "@/lib/csv";
+import { looksLikeSensitiveBlob } from "@/lib/secureLogging";
+import { isValidStrKey } from "@/lib/stellarAddress";
 import type { AnalyticsSummary, AnalyticsVolumePoint, AnalyticsRouteEntry } from "@/lib/analytics";
 
 // ─── CSV export ────────────────────────────────────────────────────────────────
@@ -87,6 +89,12 @@ export function buildAnalyticsCsvBundle(
 
 // ─── Shareable URL state ──────────────────────────────────────────────────────
 
+/**
+ * Audit (#648): the CSV bundle holds only aggregates (KPI totals, daily volume,
+ * source-chain/destination-token route totals) — no addresses, XDR or
+ * signatures. Share state is filter/view state only. Every value is bounded and
+ * must not look like a Stellar address or XDR blob, enforced on decode.
+ */
 export type AnalyticsShareState = {
   /** Date range start ISO string */
   from?: string;
@@ -99,6 +107,17 @@ export type AnalyticsShareState = {
 };
 
 const SHARE_PARAM = "av"; // analytics-view — short to keep URLs tidy
+const MAX_SHARE_PARAM_LENGTH = 1024;
+const MAX_SHARE_VALUE_LENGTH = 64;
+
+/** True when a share-state value is bounded and carries no address/XDR-shaped data. */
+function isSafeShareValue(v: string): boolean {
+  return (
+    v.length <= MAX_SHARE_VALUE_LENGTH &&
+    !isValidStrKey(v) &&
+    !looksLikeSensitiveBlob(v)
+  );
+}
 
 /**
  * Encode analytics filter state into a URL search-param string.
@@ -106,10 +125,10 @@ const SHARE_PARAM = "av"; // analytics-view — short to keep URLs tidy
  */
 export function encodeShareState(state: AnalyticsShareState): string {
   const compact: Record<string, string> = {};
-  if (state.from) compact.f = state.from;
-  if (state.to) compact.t = state.to;
-  if (state.chain) compact.c = state.chain;
-  if (state.token) compact.tk = state.token;
+  if (state.from && isSafeShareValue(state.from)) compact.f = state.from;
+  if (state.to && isSafeShareValue(state.to)) compact.t = state.to;
+  if (state.chain && isSafeShareValue(state.chain)) compact.c = state.chain;
+  if (state.token && isSafeShareValue(state.token)) compact.tk = state.token;
   return btoa(JSON.stringify(compact));
 }
 
@@ -118,19 +137,20 @@ export function encodeShareState(state: AnalyticsShareState): string {
  * Returns null if the param is missing, malformed, or contains unexpected keys.
  */
 export function decodeShareState(raw: string | null): AnalyticsShareState | null {
-  if (!raw) return null;
+  if (!raw || raw.length > MAX_SHARE_PARAM_LENGTH) return null;
   try {
     const decoded = JSON.parse(atob(raw)) as Record<string, unknown>;
+    if (!decoded || typeof decoded !== "object" || Array.isArray(decoded)) return null;
     const ALLOWED_KEYS = new Set(["f", "t", "c", "tk"]);
     // Validate — reject if any unexpected key is present
     for (const key of Object.keys(decoded)) {
       if (!ALLOWED_KEYS.has(key)) return null;
     }
     const state: AnalyticsShareState = {};
-    if (typeof decoded.f === "string") state.from = decoded.f;
-    if (typeof decoded.t === "string") state.to = decoded.t;
-    if (typeof decoded.c === "string") state.chain = decoded.c;
-    if (typeof decoded.tk === "string") state.token = decoded.tk;
+    if (typeof decoded.f === "string" && isSafeShareValue(decoded.f)) state.from = decoded.f;
+    if (typeof decoded.t === "string" && isSafeShareValue(decoded.t)) state.to = decoded.t;
+    if (typeof decoded.c === "string" && isSafeShareValue(decoded.c)) state.chain = decoded.c;
+    if (typeof decoded.tk === "string" && isSafeShareValue(decoded.tk)) state.token = decoded.tk;
     return state;
   } catch {
     return null;
diff --git a/src/lib/intentExport.ts b/src/lib/intentExport.ts
index 2a40d4e..e57b40a 100644
--- a/src/lib/intentExport.ts
+++ b/src/lib/intentExport.ts
@@ -1,3 +1,4 @@
+import { looksLikeSensitiveBlob } from "@/lib/secureLogging";
 import { sanitizeDisplayText } from "@/lib/textSafety";
 import type { IntentDetail } from "@/lib/types";
 
@@ -8,7 +9,9 @@ const REDACTED_KEY_RE = /xdr|signature|secret/i;
 
 /** Deep copy with XDR/signature-like keys removed and strings made display-safe. */
 export function redactForExport(value: unknown): unknown {
-  if (typeof value === "string") return sanitizeDisplayText(value);
+  if (typeof value === "string") {
+    return looksLikeSensitiveBlob(value) ? "[redacted]" : sanitizeDisplayText(value);
+  }
   if (Array.isArray(value)) return value.map(redactForExport);
   if (typeof value === "object" && value !== null) {
     return Object.fromEntries(
diff --git a/src/lib/knownAddresses.ts b/src/lib/knownAddresses.ts
index 0c4f457..e6557aa 100644
--- a/src/lib/knownAddresses.ts
+++ b/src/lib/knownAddresses.ts
@@ -5,6 +5,7 @@
  * the storage facade; purged after the retention in `STORAGE_KEYS`.
  */
 
+import { isValidStellarPublicKey } from "./stellarAddress";
 import { STORAGE_KEYS, storage } from "./storage";
 
 export type KnownAddressSource = "wallet" | "destination" | "solver";
@@ -24,7 +25,8 @@ export function getKnownAddressRecords(): KnownAddress[] {
   if (!Array.isArray(parsed)) return [];
   return parsed.filter(
     (e): e is KnownAddress =>
-      !!e && typeof e === "object" && typeof (e as KnownAddress).address === "string",
+      !!e && typeof e === "object" && typeof (e as KnownAddress).address === "string" &&
+      isValidStellarPublicKey((e as KnownAddress).address),
   );
 }
 
@@ -33,7 +35,7 @@ export function getKnownAddresses(): string[] {
 }
 
 export function recordKnownAddress(address: string, source: KnownAddressSource): void {
-  if (!address) return;
+  if (!address || !isValidStellarPublicKey(address)) return;
   const rest = getKnownAddressRecords().filter((e) => e.address !== address);
   const next = [{ address, source, lastSeen: Date.now() }, ...rest].slice(0, MAX_KNOWN_ADDRESSES);
   storage.setJSON(KEY, next);
diff --git a/src/lib/secureLogging.ts b/src/lib/secureLogging.ts
index e69de29..ffe2cca 100644
--- a/src/lib/secureLogging.ts
+++ b/src/lib/secureLogging.ts
@@ -0,0 +1,11 @@
+/** Heuristics for strings that look like XDR envelopes or signatures. */
+
+// Base64 run long enough to be a transaction envelope or signature, not prose.
+const BASE64_BLOB_RE = /^[A-Za-z0-9+/_-]{80,}={0,2}$/;
+// Hex run long enough to be a signature (64 bytes = 128 hex chars).
+const HEX_BLOB_RE = /^(?:0x)?[0-9a-fA-F]{128,}$/;
+
+export function looksLikeSensitiveBlob(value: string): boolean {
+  const v = value.trim();
+  return BASE64_BLOB_RE.test(v) || HEX_BLOB_RE.test(v);
+}
diff --git a/src/lib/securityHardening.test.ts b/src/lib/securityHardening.test.ts
new file mode 100644
index 0000000..1445b55
--- /dev/null
+++ b/src/lib/securityHardening.test.ts
@@ -0,0 +1,67 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { Keypair } from "@stellar/stellar-sdk";
+
+const hostname = vi.hoisted(() => ({ value: "app.test" }));
+vi.mock("@/lib/config", () => ({
+  getTrustedOrigins: () => [],
+  evaluateOrigin: (h: string) => (h === "app.test" ? "trusted" : "untrusted"),
+}));
+
+vi.mock("@/lib/textSafety", () => ({ sanitizeDisplayText: (v: string) => v }));
+vi.mock("@/store/wallet", () => ({ useWalletStore: { getState: () => ({}) } }));
+const store = vi.hoisted(() => ({ data: undefined as unknown }));
+vi.mock("@/lib/storage", () => ({
+  STORAGE_KEYS: { knownAddresses: { key: "known" } },
+  storage: { getJSON: () => store.data, setJSON: (_k: string, v: unknown) => void (store.data = v) },
+}));
+
+import { checkOriginTrusted, UntrustedOriginError } from "@/lib/wallet/assertWalletReady";
+import { getKnownAddressRecords, recordKnownAddress } from "@/lib/knownAddresses";
+import { redactForExport } from "@/lib/intentExport";
+import { decodeShareState, encodeShareState } from "@/lib/export/analyticsExport";
+
+const ADDR = Keypair.random().publicKey();
+const BLOB = "A".repeat(120);
+
+beforeEach(() => {
+  hostname.value = "app.test";
+  store.data = undefined;
+  vi.stubGlobal("window", { location: { get hostname() { return hostname.value; }, protocol: "https:" } });
+});
+
+describe("#645 origin re-check", () => {
+  it("catches a mid-flow origin change", () => {
+    expect(() => checkOriginTrusted()).not.toThrow();
+    hostname.value = "evil.test";
+    expect(() => checkOriginTrusted()).toThrow(UntrustedOriginError);
+  });
+});
+
+describe("#646 known addresses", () => {
+  it("rejects invalid addresses on write and drops them on read", () => {
+    recordKnownAddress("not-an-address", "wallet");
+    expect(getKnownAddressRecords()).toEqual([]);
+    recordKnownAddress(ADDR, "wallet");
+    expect(getKnownAddressRecords().map((e) => e.address)).toEqual([ADDR]);
+  });
+});
+
+describe("#647 value-shape redaction", () => {
+  it("redacts blob values under unrelated keys", () => {
+    expect(redactForExport({ envelope: BLOB, memo: "hello" })).toEqual({ envelope: "[redacted]", memo: "hello" });
+  });
+});
+
+describe("#648 analytics share state", () => {
+  it("never encodes address/XDR-shaped values", () => {
+    const out = atob(encodeShareState({ chain: ADDR, token: BLOB, from: "2026-01-01" }));
+    expect(out).not.toContain(ADDR);
+    expect(out).not.toContain(BLOB);
+    expect(out).toContain("2026-01-01");
+  });
+  it("rejects oversized or unsafe input on decode", () => {
+    expect(decodeShareState("A".repeat(2000))).toBeNull();
+    expect(decodeShareState(btoa(JSON.stringify({ c: ADDR })))).toEqual({});
+    expect(decodeShareState(btoa("[]"))).toBeNull();
+  });
+});
diff --git a/src/lib/stellarAddress.ts b/src/lib/stellarAddress.ts
index 7a67487..b32b265 100644
--- a/src/lib/stellarAddress.ts
+++ b/src/lib/stellarAddress.ts
@@ -182,5 +182,3 @@ export function isValidStrKey(value: string): boolean {
     decoded[decoded.length - 1] === expectedChecksum >>> 8
   );
 }
-
-}
diff --git a/src/lib/wallet/assertWalletReady.ts b/src/lib/wallet/assertWalletReady.ts
index 3ff6bcd..36db92b 100644
--- a/src/lib/wallet/assertWalletReady.ts
+++ b/src/lib/wallet/assertWalletReady.ts
@@ -10,6 +10,19 @@ export class UntrustedOriginError extends Error {
   }
 }
 
+/**
+ * Throws `UntrustedOriginError` unless the current origin is trusted. Cheap and
+ * synchronous: call it again immediately before `signTransaction` to close the
+ * gap between the precondition check and the actual signing call.
+ */
+export function checkOriginTrusted(): void {
+  const hostname = window.location.hostname;
+  const protocol = window.location.protocol.replace(":", "");
+  if (evaluateOrigin(hostname, protocol, getTrustedOrigins()) === "untrusted") {
+    throw new UntrustedOriginError(hostname);
+  }
+}
+
 /**
  * Precondition check before any wallet signing operation.
  *
@@ -27,14 +40,7 @@ export function assertWalletReady(): { address: string; network: string } {
     throw new Error(state.error ?? "Connect a wallet to continue.");
   }
 
-  const hostname = window.location.hostname;
-  const protocol = window.location.protocol.replace(":", "");
-  const trusted = getTrustedOrigins();
-  const trustLevel = evaluateOrigin(hostname, protocol, trusted);
-
-  if (trustLevel === "untrusted") {
-    throw new UntrustedOriginError(hostname);
-  }
+  checkOriginTrusted();
 
   return { address: state.address, network: state.network ?? "" };
 }