security: fix 7 audit findings (MCP server, hooks, CI)

.github/workflows/ci.yml

@@ -13,8 +13,8 @@ jobs:
       matrix:
         python-version: ["3.9", "3.11", "3.13"]
     steps:
-      - uses: actions/checkout@v6
-      - uses: actions/setup-python@v6
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
       - run: pip install -e ".[dev]"
@@ -23,8 +23,8 @@ jobs:
   test-windows:
     runs-on: windows-latest
     steps:
-      - uses: actions/checkout@v6
-      - uses: actions/setup-python@v6
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
         with:
           python-version: "3.9"
       - run: pip install -e ".[dev]"
@@ -33,17 +33,17 @@ jobs:
   test-macos:
     runs-on: macos-latest
     steps:
-      - uses: actions/checkout@v6
-      - uses: actions/setup-python@v6
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
         with:
           python-version: "3.9"
       - run: pip install -e ".[dev]"
       - run: python -m pytest tests/ -v --ignore=tests/benchmarks --cov=mempalace --cov-report=term-missing --cov-fail-under=80
   lint:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
-      - uses: actions/setup-python@v6
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
         with:
           python-version: "3.11"
       - run: pip install "ruff>=0.4.0,<0.5"

mempalace/hooks_cli.py

@@ -90,6 +90,12 @@ def _output(data: dict):
 def _maybe_auto_ingest():
     """If MEMPAL_DIR is set and exists, run mempalace mine in background."""
     mempal_dir = os.environ.get("MEMPAL_DIR", "")
+    if mempal_dir:
+        # Resolve to real path to prevent symlink traversal to sensitive directories
+        try:
+            mempal_dir = os.path.realpath(mempal_dir)
+        except (OSError, ValueError):
+            return
     if mempal_dir and os.path.isdir(mempal_dir):
         try:
             log_path = STATE_DIR / "hook.log"
@@ -187,6 +193,11 @@ def hook_precompact(data: dict, harness: str):
 
     # Optional: auto-ingest synchronously before compaction (so memories land first)
     mempal_dir = os.environ.get("MEMPAL_DIR", "")
+    if mempal_dir:
+        try:
+            mempal_dir = os.path.realpath(mempal_dir)
+        except (OSError, ValueError):
+            mempal_dir = ""
     if mempal_dir and os.path.isdir(mempal_dir):
         try:
             log_path = STATE_DIR / "hook.log"