docs(security): add 2026-10-12 audit log; refresh NIP-05 and popup rendering notes

Summarises the code review + dependency scan: no exploitable client/server issue found; documents why npm audit fix was reverted (broke the build) and which advisories are unreachable/accepted (xlsx export-only, HashRouter open-redirect, MCP client-side, build-tool deps). Fixes the outdated 'never innerHTML' claim (popups use innerHTML with escapeHtml) and updates the contact NIP-05 to the seeded skatespots@skate-spots.org.

SECURITY.md

@@ -18,7 +18,7 @@ Please report privately first — **do not** open a public issue or publish a Po
 before we've had a chance to respond.
 
 - **Nostr DM (preferred):** `npub1yrnuj56rnen08zp2h9h7p74ghgjx6ma39spmpj6w9hzxywutevsst7k5cx`
-- **NIP-05:** `skatespots@goskatespots.nostr1.com`
+- **NIP-05:** `skatespots@skate-spots.org` (seeded platform handle)
 
 Please include:
 
@@ -178,10 +178,10 @@ Additional headers: `X-Content-Type-Options: nosniff`,
 - **React/JSX** auto-escapes all interpolated strings — the default rendering
   path. Do not bypass it.
 - **Leaflet map popups & marker icons** (`src/components/SpotMap.tsx`) are the
-  one place we build DOM by hand. Every untrusted field (spot/tour/crew/event
-  titles & locations, meeting points, BTC Map name/address/hours/phone/
-  description) is written via `textContent`, never `innerHTML`. A `popupRow()`
-  helper enforces this. Image/website fields are validated before use.
+  one place we build DOM by hand. Popups set `innerHTML` from a template in which
+  **every dynamic value is passed through `escapeHtml`** (re-verified 2026-10-12);
+  marker icons and the weather card use `textContent`. Image/website fields are
+  validated before use.
 - Rich Nostr note content is rendered through the shared `NoteContent`
   component/tokenizer rather than raw HTML.
 
@@ -294,6 +294,62 @@ stronger handling than other secrets:
 
 ---
 
+---
+
+## Audit log — 2026-10-12 (code review + dependency scan)
+
+A targeted review of the client (`src/`), the standalone servers (`cvm-server`,
+`push-service`, `ai-proxy`, `netlify/functions`) and the dependency tree.
+
+**No exploitable issue was found in app code.**
+
+- **Injection / XSS:** no `eval` / `new Function`; `dangerouslySetInnerHTML`
+  appears only in shadcn's `chart.tsx` (static, developer-defined chart CSS). The
+  hand-built Leaflet popup HTML interpolates values but every dynamic value is
+  `escapeHtml`'d (verified). `document.write` (recovery-phrase QR and rider-card
+  print windows) interpolates only canvas data-URLs and i18n strings. No
+  `__proto__` / prototype pollution. No secrets in web storage beyond the
+  documented `nsec`/NWC/Cashu.
+- **Reverse tabnabbing:** every `target="_blank"` also carries
+  `rel="noopener noreferrer"`.
+- **SSRF:** the only `fetch` to a derived host is
+  `https://<domain>/.well-known/lnurlp/…` where the domain comes from a
+  **hardcoded platform Lightning address** (not user input). Servers do not fetch
+  user-supplied URLs. The push service additionally validates subscription
+  endpoints (`isSafePushEndpoint`: https-only; blocks localhost + private /
+  link-local / CGNAT ranges).
+- **Auth:** NIP-98 (kind 27235) signature + timestamp checks gate push
+  subscribe/unregister and the AI proxy; zap receipts and owner-grant labels are
+  signature-verified (`verifyEvent`) on both client and servers; the CVM server
+  signature-verifies event content before serving it to agents.
+- **CORS:** the AI proxy and push service enforce origin allowlists; the NIP-05
+  well-known function is intentionally `Access-Control-Allow-Origin: *` (public).
+- **Randomness:** `Math.random` is used only for UI ids, probe/subscription ids,
+  PoW nonces and privacy timestamp jitter — never for secrets or tokens.
+
+**Dependencies (`npm audit`).** `npm audit fix` updated `@remix-run/router` (open
+redirect), `@modelcontextprotocol/sdk`, `@humanfs/node`, `valibot` and
+`brace-expansion`, but was **reverted** because it re-resolved the lockfile and
+broke the build (a nested `@nostrify/nostrify` duplicate introduced a type
+conflict). Re-assessment: none of the remaining advisories is reachable from the
+shipped app —
+
+- `xlsx` (high, prototype pollution + ReDoS, no fix): used only to **generate** the
+  deck-cost workbook (`XLSX.writeFile`); imported files are never **parsed**, so
+  the parsing flaws are unreachable. Accepted.
+- `@remix-run/router` open redirect: unreachable — the app uses **HashRouter**, so
+  navigation stays inside the `#` fragment and never crosses to an external URL.
+- `@modelcontextprotocol/sdk` OAuth flaw: affects MCP **clients** connecting to
+  untrusted servers; `cvm-server` is an MCP **server**, not a client. Not
+  applicable.
+- `braces`, `@vitest/mocker`, `@capacitor/cli`'s `uuid`, `tailwindcss`: build/test
+  tooling only — no runtime reach into the served app. Accepted.
+
+A broken build is a larger risk than an unreachable CVE, so the broken fix was
+reverted rather than forced through.
+
+---
+
 ## For auditors: where to look first
 
 | Area | Files |