From 868fa9566a855e316e79a3921ac0a55cd68a380f Mon Sep 17 00:00:00 2001
From: Teknium <127238744+teknium1@users.noreply.github.com>
Date: Wed, 1 Jul 2026 02:14:14 -0700
Subject: [PATCH] fix(security): block /proc/*/auxv and /proc/*/pagemap read
 leaks
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auxv leaks AT_RANDOM (stack canary seed) + AT_BASE/AT_PHDR load
addresses — an ASLR oracle on par with maps. pagemap exposes
virtual->physical translation. Both slipped through the endswith
tuple alongside the maps family covered by the salvaged commit.

Adds regression coverage for auxv/pagemap and for the per-thread
/proc/<pid>/task/<tid>/<file> alias form (endswith catches both).

Follow-up on #32238, closes #34430.
---
 tests/tools/test_file_read_guards.py | 15 +++++++++++++++
 tools/file_tools.py                  | 16 +++++++++++++++-
 2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/tests/tools/test_file_read_guards.py b/tests/tools/test_file_read_guards.py
index ad12dc78a..861ebc493 100644
--- a/tests/tools/test_file_read_guards.py
+++ b/tests/tools/test_file_read_guards.py
@@ -109,6 +109,21 @@ class TestDevicePathBlocking(unittest.TestCase):
             "/proc/1/numa_maps",
             "/proc/self/mem",
             "/proc/12345/mem",
+            "/proc/self/auxv",
+            "/proc/1/auxv",
+            "/proc/self/pagemap",
+            "/proc/99/pagemap",
+        ):
+            self.assertTrue(_is_blocked_device(path), f"{path} should be blocked")
+
+    def test_proc_task_thread_sensitive_files_blocked(self):
+        """Per-thread /proc/<pid>/task/<tid>/<file> aliases leak the same data."""
+        for path in (
+            "/proc/self/task/1234/maps",
+            "/proc/self/task/1234/smaps",
+            "/proc/self/task/1234/auxv",
+            "/proc/self/task/1234/pagemap",
+            "/proc/self/task/1234/environ",
         ):
             self.assertTrue(_is_blocked_device(path), f"{path} should be blocked")
 
diff --git a/tools/file_tools.py b/tools/file_tools.py
index b85ab9726..7bf51aa90 100644
--- a/tools/file_tools.py
+++ b/tools/file_tools.py
@@ -367,8 +367,22 @@ def _is_blocked_device_path(path: str) -> bool:
     # memory layout (ASLR bypass) from the host process (issue #4427).
     # /proc/*/mem exposes raw process memory; block it as defense-in-depth even
     # though it requires address knowledge to exploit usefully.
+    # /proc/*/auxv leaks AT_RANDOM (stack canary seed) plus AT_BASE/AT_PHDR
+    # load addresses — an ASLR oracle on par with maps. /proc/*/pagemap exposes
+    # virtual->physical translation. Both are blocked alongside the maps family.
+    # endswith matches both /proc/<pid>/X and /proc/<pid>/task/<tid>/X.
     if normalized.startswith("/proc/") and normalized.endswith(
-        ("/environ", "/cmdline", "/maps", "/smaps", "/smaps_rollup", "/numa_maps", "/mem")
+        (
+            "/environ",
+            "/cmdline",
+            "/maps",
+            "/smaps",
+            "/smaps_rollup",
+            "/numa_maps",
+            "/mem",
+            "/auxv",
+            "/pagemap",
+        )
     ):
         return True
     return False