From 88b768403495e87fd2bbe60349040d7a927734b2 Mon Sep 17 00:00:00 2001
From: joaovictor91123 <joaovictor91123@gmail.com>
Date: Thu, 16 Jul 2026 08:37:58 +0400
Subject: [PATCH] fix(mcp): redact a parenthesis/bracket/colon-prefixed local
 path in redactLocalPath

redactLocalPath's prefix delimiter class only recognized whitespace, quotes,
backtick, and "=" immediately before a local path -- missing "(", the Node.js
stack-frame shape ("at fn (/abs/path:10:5)"), so a real absolute path pasted
into validation output could leak upstream unredacted. Verified and closed
two adjacent gaps in the same class ("[" and ":") while at it, and excluded
"]" from the path-tail/segment patterns so a bracket-wrapped path redacts
cleanly instead of swallowing the closing bracket.
---
 packages/loopover-mcp/lib/redact-local-path.js |  9 ++++++---
 test/unit/redact-local-path.test.ts            | 18 ++++++++++++++++++
 2 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/packages/loopover-mcp/lib/redact-local-path.js b/packages/loopover-mcp/lib/redact-local-path.js
index ddd5745418..00379bd8a4 100644
--- a/packages/loopover-mcp/lib/redact-local-path.js
+++ b/packages/loopover-mcp/lib/redact-local-path.js
@@ -23,9 +23,12 @@ export function redactLocalPath(value) {
   // Both `/g` patterns are rebuilt per call so no `lastIndex` state carries between invocations.
   // Delimiter-anchored roots (`~/`, `~\`, `C:\`, `C:/`, `/`) whose interior segments may contain
   // spaces, e.g. `/Users/Alice Smith/project` — the anchoring prefix is preserved, only the path swaps.
-  const pathSegment = "[^\\\\/\\s\"'`,;)]+(?:\\s+[^\\\\/\\s\"'`,;)]+)*(?=[\\\\/])";
-  const pathTail = "[^\\\\/\\s\"'`,;)]+";
-  const rootedPath = new RegExp(`(^|[\\s"'\\\`=])((?:~[\\\\/]|[A-Za-z]:[\\\\/]|/)(?:${pathSegment}[\\\\/])*${pathTail})`, "g");
+  const pathSegment = "[^\\\\/\\s\"'`,;)\\]]+(?:\\s+[^\\\\/\\s\"'`,;)\\]]+)*(?=[\\\\/])";
+  const pathTail = "[^\\\\/\\s\"'`,;)\\]]+";
+  // Prefix delimiters a real path can immediately follow in pasted stack-trace/validation-output text.
+  // `(` is the Node.js stack-frame shape (`at fn (/abs/path:10:5)`); `[` and `:` cover the same "no space
+  // before the path" shape in bracketed log lines and colon-joined messages (e.g. `path:/abs/path`).
+  const rootedPath = new RegExp(`(^|[\\s"'\\\`=(\\[:])((?:~[\\\\/]|[A-Za-z]:[\\\\/]|/)(?:${pathSegment}[\\\\/])*${pathTail})`, "g");
   return text
     .replace(rootedPath, (_, prefix) => `${prefix}<local-path>`)
     // Home/Windows roots that appear mid-token with no leading delimiter (so the anchored pass skips
diff --git a/test/unit/redact-local-path.test.ts b/test/unit/redact-local-path.test.ts
index 1e988ea202..6b9ef3601c 100644
--- a/test/unit/redact-local-path.test.ts
+++ b/test/unit/redact-local-path.test.ts
@@ -30,6 +30,24 @@ describe("redactLocalPath (heuristic: detect an unknown path in free text)", ()
     expect(redacted).not.toContain("~/private");
   });
 
+  // #6258: a Node.js stack-frame path (`at fn (/abs/path:line:col)`) previously leaked in full because
+  // `(` was missing from the prefix delimiter class -- only a space-prefixed path redacted correctly.
+  it("redacts a parenthesis-prefixed path (the Node.js stack-frame shape)", () => {
+    // The trailing `:10:5` line/column suffix has no path separator before the closing `)`, so it's
+    // swallowed into the same redacted match -- still a full, leak-free redaction either way.
+    expect(redactLocalPath("at Object.<anonymous> (/Users/alice/secretproject/file.js:10:5)")).toBe(
+      "at Object.<anonymous> (<local-path>)",
+    );
+  });
+
+  it("redacts a bracket-prefixed path, preserving the closing bracket", () => {
+    expect(redactLocalPath("[/Users/alice/secretproject/file.js]")).toBe("[<local-path>]");
+  });
+
+  it("redacts a colon-prefixed path with no space (e.g. `label:/abs/path`)", () => {
+    expect(redactLocalPath("error:/Users/alice/secretproject/file.js")).toBe("error:<local-path>");
+  });
+
   it("leaves text with no local path untouched, including a bare slash", () => {
     expect(redactLocalPath("just some text, version 1.2.3")).toBe("just some text, version 1.2.3");
     expect(redactLocalPath("pass --flag / or | here")).toBe("pass --flag / or | here");