From e1bc5cad25b0906945efec52fb81314b590caec2 Mon Sep 17 00:00:00 2001
From: Peter Steinberger <steipete@gmail.com>
Date: Mon, 2 Mar 2026 19:27:50 +0000
Subject: [PATCH] fix(outbound): harden plain-text HTML sanitization paths
 (#32034)

---
 src/infra/outbound/deliver.test.ts       | 49 ++++++++++++++++++++++++
 src/infra/outbound/deliver.ts            | 32 ++++++++++++----
 src/infra/outbound/sanitize-text.test.ts |  6 +++
 src/infra/outbound/sanitize-text.ts      |  2 +
 4 files changed, 82 insertions(+), 7 deletions(-)

diff --git a/src/infra/outbound/deliver.test.ts b/src/infra/outbound/deliver.test.ts
index 71acf883b..79b1ba746 100644
--- a/src/infra/outbound/deliver.test.ts
+++ b/src/infra/outbound/deliver.test.ts
@@ -221,6 +221,30 @@ describe("deliverOutboundPayloads", () => {
     );
   });
 
+  it("preserves HTML text for telegram sendPayload channelData path", async () => {
+    const sendTelegram = vi.fn().mockResolvedValue({ messageId: "m1", chatId: "c1" });
+
+    await deliverOutboundPayloads({
+      cfg: telegramChunkConfig,
+      channel: "telegram",
+      to: "123",
+      payloads: [
+        {
+          text: "<b>hello</b>",
+          channelData: { telegram: { buttons: [] } },
+        },
+      ],
+      deps: { sendTelegram },
+    });
+
+    expect(sendTelegram).toHaveBeenCalledTimes(1);
+    expect(sendTelegram).toHaveBeenCalledWith(
+      "123",
+      "<b>hello</b>",
+      expect.objectContaining({ textMode: "html" }),
+    );
+  });
+
   it("scopes media local roots to the active agent workspace when agentId is provided", async () => {
     const sendTelegram = vi.fn().mockResolvedValue({ messageId: "m1", chatId: "c1" });
 
@@ -442,6 +466,17 @@ describe("deliverOutboundPayloads", () => {
     expect(results).toEqual([]);
   });
 
+  it("drops HTML-only WhatsApp text payloads after sanitization", async () => {
+    const sendWhatsApp = vi.fn().mockResolvedValue({ messageId: "w1", toJid: "jid" });
+    const results = await deliverWhatsAppPayload({
+      sendWhatsApp,
+      payload: { text: "<br><br>" },
+    });
+
+    expect(sendWhatsApp).not.toHaveBeenCalled();
+    expect(results).toEqual([]);
+  });
+
   it("keeps WhatsApp media payloads but clears whitespace-only captions", async () => {
     const sendWhatsApp = vi.fn().mockResolvedValue({ messageId: "w1", toJid: "jid" });
     await deliverWhatsAppPayload({
@@ -461,6 +496,20 @@ describe("deliverOutboundPayloads", () => {
     );
   });
 
+  it("drops non-WhatsApp HTML-only text payloads after sanitization", async () => {
+    const sendSignal = vi.fn().mockResolvedValue({ messageId: "s1", toJid: "jid" });
+    const results = await deliverOutboundPayloads({
+      cfg: {},
+      channel: "signal",
+      to: "+1555",
+      payloads: [{ text: "<br>" }],
+      deps: { sendSignal },
+    });
+
+    expect(sendSignal).not.toHaveBeenCalled();
+    expect(results).toEqual([]);
+  });
+
   it("preserves fenced blocks for markdown chunkers in newline mode", async () => {
     const chunker = vi.fn((text: string) => (text ? [text] : []));
     const sendText = vi.fn().mockImplementation(async ({ text }: { text: string }) => ({
diff --git a/src/infra/outbound/deliver.ts b/src/infra/outbound/deliver.ts
index 1fd5f3de7..c5b986bae 100644
--- a/src/infra/outbound/deliver.ts
+++ b/src/infra/outbound/deliver.ts
@@ -446,14 +446,21 @@ async function deliverOutboundPayloadsCore(
       text: normalizedText,
     };
   };
-  const normalizedPayloads = normalizeReplyPayloadsForDelivery(payloads)
-    .flatMap((payload) => {
-      if (channel !== "whatsapp") {
-        return [payload];
+  const normalizeEmptyTextPayload = (payload: ReplyPayload): ReplyPayload | null => {
+    const hasMedia = Boolean(payload.mediaUrl) || (payload.mediaUrls?.length ?? 0) > 0;
+    const rawText = typeof payload.text === "string" ? payload.text : "";
+    if (!rawText.trim()) {
+      if (!hasMedia) {
+        return null;
       }
-      const normalized = normalizeWhatsAppPayload(payload);
-      return normalized ? [normalized] : [];
-    })
+      return {
+        ...payload,
+        text: "",
+      };
+    }
+    return payload;
+  };
+  const normalizedPayloads = normalizeReplyPayloadsForDelivery(payloads)
     .map((payload) => {
       // Strip HTML tags for plain-text surfaces (WhatsApp, Signal, etc.)
       // Models occasionally produce <br>, <b>, etc. that render as literal text.
@@ -461,7 +468,18 @@ async function deliverOutboundPayloadsCore(
       if (!isPlainTextSurface(channel) || !payload.text) {
         return payload;
       }
+      // Telegram sendPayload uses textMode:"html". Preserve raw HTML in this path.
+      if (channel === "telegram" && payload.channelData) {
+        return payload;
+      }
       return { ...payload, text: sanitizeForPlainText(payload.text) };
+    })
+    .flatMap((payload) => {
+      const normalized =
+        channel === "whatsapp"
+          ? normalizeWhatsAppPayload(payload)
+          : normalizeEmptyTextPayload(payload);
+      return normalized ? [normalized] : [];
     });
   const hookRunner = getGlobalHookRunner();
   const sessionKeyForInternalHooks = params.mirror?.sessionKey ?? params.session?.key;
diff --git a/src/infra/outbound/sanitize-text.test.ts b/src/infra/outbound/sanitize-text.test.ts
index c7aebb6db..b22b45df2 100644
--- a/src/infra/outbound/sanitize-text.test.ts
+++ b/src/infra/outbound/sanitize-text.test.ts
@@ -85,6 +85,12 @@ describe("sanitizeForPlainText", () => {
     expect(sanitizeForPlainText('<a href="https://example.com">link</a>')).toBe("link");
   });
 
+  it("preserves angle-bracket autolinks", () => {
+    expect(sanitizeForPlainText("See <https://example.com/path?q=1> now")).toBe(
+      "See https://example.com/path?q=1 now",
+    );
+  });
+
   // --- passthrough --------------------------------------------------------
 
   it("passes through clean text unchanged", () => {
diff --git a/src/infra/outbound/sanitize-text.ts b/src/infra/outbound/sanitize-text.ts
index fb6b6abbb..84adfda3a 100644
--- a/src/infra/outbound/sanitize-text.ts
+++ b/src/infra/outbound/sanitize-text.ts
@@ -38,6 +38,8 @@ export function isPlainTextSurface(channelId: string): boolean {
 export function sanitizeForPlainText(text: string): string {
   return (
     text
+      // Preserve angle-bracket autolinks as plain URLs before tag stripping.
+      .replace(/<((?:https?:\/\/|mailto:)[^<>\s]+)>/gi, "$1")
       // Line breaks
       .replace(/<br\s*\/?>/gi, "\n")
       // Block elements → newlines