diff --git a/plugins/secretscan.lua b/plugins/secretscan.lua
new file mode 100644
index 0000000..afbf87c
--- /dev/null
+++ b/plugins/secretscan.lua
@@ -0,0 +1,166 @@
+Plugin = {
+  name        = "Secret Scan",
+  description = [[
+Scans HTML, JavaScript and JSON content (requests and responses) for hardcoded
+secrets by matching common secret key names followed by a non-trivial value.
+
+Uses `grep -E` (available on all Unix systems, no extra dependencies).
+  ]],
+  on_request  = { sync = false },
+  on_response = { sync = false },
+  disable_by_default = true,
+}
+
+local CONTENT_TYPES = {
+  "text/html",
+  "text/javascript",
+  "application/javascript",
+  "application/json",
+}
+
+-- Key name alternation (case-insensitive via grep -i)
+-- Suffixes are required (no bare generic keyword alone).
+local KEYS = {
+  "access(_key|_token)", "accessid_secret", "account(_key|_sid)",
+  "admin_pass(word)?", "admin_user",
+  "(algolia|aws|gcp|azure|heroku|firebase|github|gitlab|slack|datadog|stripe|twilio|vercel|supabase|sendgrid|cloudinary|cloudflare|bitbucket|npm|netlify|auth0|okta|sentry)(_?(api|secret|access)(_?(key|token|id|sid|secret))?|_?(key|token|id|sid|secret))",
+  "ansible_vault_password", "aos_key",
+  "api(_key|_secret|_token)",
+  "app_(id|key|secret)", "application(_key|_id|_secret)",
+  "auth(_token|_secret|orization)", "authkey", "authsecret",
+  "bearer_?token",
+  "bucket(_password|_key)",
+  "cert_?pass(word)?", "certificate_password",
+  "client(_id|_secret)",
+  "codecov_token", "consumer_(key|secret)",
+  "connection_?string", "credentials?", "crypt(_key|_secret)",
+  "db_(password|passwd|user(name)?)",
+  "deploy(_key|_password|_token)",
+  "docker_?pass(word)?", "dockerhub_?password",
+  "encryption_(key|password)",
+  "jwt_secret", "json_web_token",
+  "keycloak_secret", "kubernetes_token",
+  "ldap_(password|bindpw)", "login(_password|_token)",
+  "mail_?password", "mail_smtp_pass",
+  "mysql_password", "mongo_password",
+  "netlify_token", "npm(_token|_auth_token)",
+  "oauth(_token|_secret)",
+  "openai_(api_key|secret)",
+  "pass(word)?", "passwd",
+  "private(_key|_token)",
+  "rds_password",
+  "s3(_key|_secret|_access_key_id)",
+  "secret(_key|_token|_id)", "security_token",
+  "sendgrid_api_key",
+  "ses_(smtp|access|secret)",
+  "service(_account|_key|_token)",
+  "smtp_pass(word)?", "smtp_secret",
+  "sonar_token",
+  "ssh(_key|_private_key|_rsa)",
+  "supabase(_anon|_service)?_key",
+  "symfony_secret",
+  "telegram_bot_token",
+  "token",
+  "travis_token",
+  "vault(_token|_secret)",
+  "webhook(_secret|_token)",
+  "zapier_webhook_token",
+}
+
+-- Built once at load time.
+-- Pattern breakdown:
+--   KEY[a-z0-9._-]{0,20}   key name + optional alphanumeric suffix (e.g. _ID in AWS_ACCESS_KEY_ID)
+--   [^=:a-zA-Z0-9_]{0,3}  optional non-identifier chars before separator (e.g. closing " in JSON "key":)
+--   [[:space:]]*[:=]        REQUIRED: actual = or : assignment operator
+--   [[:space:]]*"?          optional whitespace + opening quote
+--   [a-zA-Z0-9+/=_.-]{8,} the secret value, at least 8 chars
+local KEY_PAT  = "(" .. table.concat(KEYS, "|") .. ")"
+local FULL_PAT = KEY_PAT .. '[a-z0-9._-]{0,20}[^=:a-zA-Z0-9_]{0,3}[[:space:]]*[:=][[:space:]]*"?[a-zA-Z0-9+/=_.-]{8,}'
+local GREP_CMD = "grep -Eoni '" .. FULL_PAT .. "'"
+
+local function is_relevant(ct)
+  if not ct or ct == "" then return false end
+  ct = ct:lower()
+  for _, t in ipairs(CONTENT_TYPES) do
+    if ct:find(t, 1, true) then return true end
+  end
+  return false
+end
+
+local function build_context(lines, linenum)
+  local lo = math.max(1, linenum - 6)
+  local hi = math.min(#lines, linenum + 6)
+
+  local before, after = {}, {}
+  for i = lo, linenum - 1 do
+    local l = lines[i] or ""
+    if #l > 120 then l = l:sub(1, 120) .. "..." end
+    table.insert(before, l)
+  end
+  for i = linenum + 1, hi do
+    local l = lines[i] or ""
+    if #l > 120 then l = l:sub(1, 120) .. "..." end
+    table.insert(after, l)
+  end
+
+  local matched_line = lines[linenum] or ""
+  if #matched_line > 200 then matched_line = matched_line:sub(1, 200) .. "..." end
+
+  local parts = {}
+  if #before > 0 then
+    table.insert(parts, "```\n" .. table.concat(before, "\n") .. "\n```")
+  end
+  table.insert(parts, "> **`" .. matched_line .. "`**")
+  if #after > 0 then
+    table.insert(parts, "```\n" .. table.concat(after, "\n") .. "\n```")
+  end
+  return table.concat(parts, "\n\n")
+end
+
+local function scan(label, ct, body, host, path)
+  if not is_relevant(ct) then return end
+  if not body or body == "" then return end
+
+  local out, err = shell_pipe(GREP_CMD, body)
+  if err and err ~= "" then
+    log("grep error on " .. label .. " for " .. host .. path .. ": " .. err)
+    return
+  end
+  if not out or out == "" then return end
+
+  local lines = {}
+  for line in (body .. "\n"):gmatch("([^\n]*)\n") do
+    table.insert(lines, line)
+  end
+
+  for entry in out:gmatch("[^\n]+") do
+    local linenum_str, matched = entry:match("^(%d+):(.+)$")
+    if linenum_str then
+      local linenum = tonumber(linenum_str)
+      matched = matched:match("^%s*(.-)%s*$")
+      if matched ~= "" then
+        local display = matched
+        if #display > 200 then display = display:sub(1, 200) .. "..." end
+        local ctx = build_context(lines, linenum)
+        create_finding({
+          title       = "Potential secret in " .. label .. " (" .. host .. ")",
+          description = "**Host:** `" .. host .. "`  \n**Path:** `" .. path .. "`\n\n**Match:** `" .. display .. "`\n\n" .. ctx,
+          key         = host .. "|" .. path .. "|" .. label .. "|" .. matched,
+          severity    = "high",
+        })
+      end
+    end
+  end
+end
+
+function on_request(req)
+  scan("request", req.headers["Content-Type"] or "", req:get_body(), req.host, req.path)
+end
+
+function on_response(req, res)
+  local ct = ""
+  if res.headers then
+    ct = res.headers["Content-Type"] or ""
+  end
+  scan("response", ct, res:get_body(), req.host, req.path)
+end