From b4059af8270e9925fc7be2222c03bb3075bea5f8 Mon Sep 17 00:00:00 2001
From: clawbot <35+clawbot@noreply.example.org>
Date: Wed, 14 Oct 2026 10:48:41 +0200
Subject: [PATCH] fix: a listed site ending in a dot gets the phishing warning
 (closes #534)

The blocklist check hashed the hostname as the page gave it, so
"myetheywallet.com." and every subdomain written that way hashed
differently from the listed "myetheywallet.com" and opened approval
prompts with no warning. The browser and DNS treat both spellings as
one host. hostnameVariants() now drops one trailing dot before
building the hostname and its parent domains, so the check sees the
name the list holds.

Model: opus-5-5
---
 README.md                     |  3 ++-
 src/shared/phishingDomains.js |  5 ++++-
 tests/phishingDomains.test.js | 13 +++++++++++++
 3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index ef7347b..54a5f07 100644
--- a/README.md
+++ b/README.md
@@ -2663,7 +2663,8 @@ plaintext list of anyone's domain names.
 When a dApp on a blocklisted domain requests a wallet connection, transaction
 approval, or signature, the approval popup displays a prominent red warning
 banner alerting the user. The domain checker matches exact hostnames and all
-parent domains (subdomain matching).
+parent domains (subdomain matching), and checks a hostname written with a
+trailing dot (`name.`) as `name`.
 
 #### Transaction Decoding
 
diff --git a/src/shared/phishingDomains.js b/src/shared/phishingDomains.js
index 6ecb953..f43f23a 100644
--- a/src/shared/phishingDomains.js
+++ b/src/shared/phishingDomains.js
@@ -110,11 +110,14 @@ function hashListed(hash) {
  * Generate hostname variants for subdomain matching.
  * "sub.evil.com" yields ["sub.evil.com", "evil.com"].
  *
+ * A trailing dot is dropped: "evil.com." is the fully qualified spelling of
+ * "evil.com", and the browser loads the same site from either.
+ *
  * @param {string} hostname
  * @returns {string[]}
  */
 function hostnameVariants(hostname) {
-    const h = hostname.toLowerCase();
+    const h = hostname.toLowerCase().replace(/\.$/, "");
     const variants = [h];
     const parts = h.split(".");
     // Parent domains: a.b.c.d -> b.c.d, c.d
diff --git a/tests/phishingDomains.test.js b/tests/phishingDomains.test.js
index e203d59..b860053 100644
--- a/tests/phishingDomains.test.js
+++ b/tests/phishingDomains.test.js
@@ -89,6 +89,12 @@ describe("vendored blocklist", () => {
         expect(isPhishingDomain(LISTED[0].toUpperCase())).toBe(true);
     });
 
+    test("a hostname ending in a dot is the same host", () => {
+        expect(isPhishingDomain(LISTED[1] + ".")).toBe(true);
+        expect(isPhishingDomain("wallet." + LISTED[1] + ".")).toBe(true);
+        expect(isPhishingDomain(CLEAN[0] + ".")).toBe(false);
+    });
+
     test("returns false for an empty or missing hostname", () => {
         expect(isPhishingDomain("")).toBe(false);
         expect(isPhishingDomain(null)).toBe(false);
@@ -133,6 +139,13 @@ describe("hostnameVariants", () => {
     test("lowercases hostnames", () => {
         expect(hostnameVariants("Evil.COM")).toEqual(["evil.com"]);
     });
+
+    test("drops the trailing dot of a fully qualified hostname", () => {
+        expect(hostnameVariants("sub.evil.com.")).toEqual([
+            "sub.evil.com",
+            "evil.com",
+        ]);
+    });
 });
 
 describe("domain hashing", () => {