fix(security): create session transcript files with 0o600 permissions (#18066)

Merged via /review-pr -> /prepare-pr -> /merge-pr.

Prepared head SHA: 962f497d242c5affa9b610f38f3dc7844426198d
Co-authored-by: brandonwise <21148772+brandonwise@users.noreply.github.com>
Co-authored-by: sebslight <19554889+sebslight@users.noreply.github.com>
Reviewed-by: @sebslight

src/security/fix.test.ts

@@ -255,6 +255,9 @@ describe("security fix", () => {
     const sessionsStorePath = path.join(sessionsDir, "sessions.json");
     await fs.writeFile(sessionsStorePath, "{}\n", "utf-8");
     await fs.chmod(sessionsStorePath, 0o644);
+    const transcriptPath = path.join(sessionsDir, "sess-main.jsonl");
+    await fs.writeFile(transcriptPath, '{"type":"session"}\n', "utf-8");
+    await fs.chmod(transcriptPath, 0o644);
 
     const env = {
       ...process.env,
@@ -269,6 +272,7 @@ describe("security fix", () => {
     expectPerms((await fs.stat(allowFromPath)).mode & 0o777, 0o600);
     expectPerms((await fs.stat(authProfilesPath)).mode & 0o777, 0o600);
     expectPerms((await fs.stat(sessionsStorePath)).mode & 0o777, 0o600);
+    expectPerms((await fs.stat(transcriptPath)).mode & 0o777, 0o600);
     expectPerms((await fs.stat(includePath)).mode & 0o777, 0o600);
   });
 });

src/security/fix.ts

@@ -366,6 +366,21 @@ async function chmodCredentialsAndAgentState(params: {
     const storePath = path.join(sessionsDir, "sessions.json");
     // eslint-disable-next-line no-await-in-loop
     params.actions.push(await params.applyPerms({ path: storePath, mode: 0o600, require: "file" }));
+
+    // Fix permissions on session transcript files (*.jsonl)
+    // eslint-disable-next-line no-await-in-loop
+    const sessionEntries = await fs.readdir(sessionsDir, { withFileTypes: true }).catch(() => []);
+    for (const entry of sessionEntries) {
+      if (!entry.isFile()) {
+        continue;
+      }
+      if (!entry.name.endsWith(".jsonl")) {
+        continue;
+      }
+      const p = path.join(sessionsDir, entry.name);
+      // eslint-disable-next-line no-await-in-loop
+      params.actions.push(await params.applyPerms({ path: p, mode: 0o600, require: "file" }));
+    }
   }
 }