fix(security): consolidated security hardening — SSRF, timing attack, tar traversal, credential leakage (#5944)

Salvaged from PRs #5800 (memosr), #5806 (memosr), #5915 (Ruzzgar), #5928 (Awsh1).

Changes:
- Use hmac.compare_digest for API key comparison (timing attack prevention)
- Apply provider env var blocklist to Docker containers (credential leakage)
- Replace tar.extractall() with safe extraction in TerminalBench2 (CVE-2007-4559)
- Add SSRF protection via is_safe_url to ALL platform adapters:
  base.py (cache_image_from_url, cache_audio_from_url),
  discord, slack, telegram, matrix, mattermost, feishu, wecom
  (Signal and WhatsApp protected via base.py helpers)
- Update tests: mock is_safe_url in Mattermost download tests
- Add security tests for tar extraction (traversal, symlinks, safe files)

tests/environments/benchmarks/test_terminalbench2_env_security.py

@@ -0,0 +1,164 @@
+"""Security tests for Terminal-Bench 2 archive extraction."""
+
+import base64
+import importlib
+import io
+import sys
+import tarfile
+import types
+
+import pytest
+
+
+def _stub_module(name: str, **attrs):
+    module = types.ModuleType(name)
+    for key, value in attrs.items():
+        setattr(module, key, value)
+    return module
+
+
+def _load_terminalbench_module(monkeypatch):
+    class _EvalHandlingEnum:
+        STOP_TRAIN = "stop_train"
+
+    class _APIServerConfig:
+        def __init__(self, *args, **kwargs):
+            self.args = args
+            self.kwargs = kwargs
+
+    class _AgentResult:
+        pass
+
+    class _HermesAgentLoop:
+        pass
+
+    class _HermesAgentBaseEnv:
+        pass
+
+    class _HermesAgentEnvConfig:
+        pass
+
+    class _ToolContext:
+        pass
+
+    stub_modules = {
+        "atroposlib": _stub_module("atroposlib"),
+        "atroposlib.envs": _stub_module("atroposlib.envs"),
+        "atroposlib.envs.base": _stub_module(
+            "atroposlib.envs.base",
+            EvalHandlingEnum=_EvalHandlingEnum,
+        ),
+        "atroposlib.envs.server_handling": _stub_module("atroposlib.envs.server_handling"),
+        "atroposlib.envs.server_handling.server_manager": _stub_module(
+            "atroposlib.envs.server_handling.server_manager",
+            APIServerConfig=_APIServerConfig,
+        ),
+        "environments.agent_loop": _stub_module(
+            "environments.agent_loop",
+            AgentResult=_AgentResult,
+            HermesAgentLoop=_HermesAgentLoop,
+        ),
+        "environments.hermes_base_env": _stub_module(
+            "environments.hermes_base_env",
+            HermesAgentBaseEnv=_HermesAgentBaseEnv,
+            HermesAgentEnvConfig=_HermesAgentEnvConfig,
+        ),
+        "environments.tool_context": _stub_module(
+            "environments.tool_context",
+            ToolContext=_ToolContext,
+        ),
+        "tools.terminal_tool": _stub_module(
+            "tools.terminal_tool",
+            register_task_env_overrides=lambda *args, **kwargs: None,
+            clear_task_env_overrides=lambda *args, **kwargs: None,
+            cleanup_vm=lambda *args, **kwargs: None,
+        ),
+    }
+
+    stub_modules["atroposlib"].envs = stub_modules["atroposlib.envs"]
+    stub_modules["atroposlib.envs"].base = stub_modules["atroposlib.envs.base"]
+    stub_modules["atroposlib.envs"].server_handling = stub_modules["atroposlib.envs.server_handling"]
+    stub_modules["atroposlib.envs.server_handling"].server_manager = stub_modules[
+        "atroposlib.envs.server_handling.server_manager"
+    ]
+
+    for name, module in stub_modules.items():
+        monkeypatch.setitem(sys.modules, name, module)
+
+    module_name = "environments.benchmarks.terminalbench_2.terminalbench2_env"
+    sys.modules.pop(module_name, None)
+    return importlib.import_module(module_name)
+
+
+def _build_tar_b64(entries):
+    buf = io.BytesIO()
+    with tarfile.open(fileobj=buf, mode="w:gz") as tar:
+        for entry in entries:
+            kind = entry["kind"]
+            info = tarfile.TarInfo(entry["name"])
+
+            if kind == "dir":
+                info.type = tarfile.DIRTYPE
+                tar.addfile(info)
+                continue
+
+            if kind == "file":
+                data = entry["data"].encode("utf-8")
+                info.size = len(data)
+                tar.addfile(info, io.BytesIO(data))
+                continue
+
+            if kind == "symlink":
+                info.type = tarfile.SYMTYPE
+                info.linkname = entry["target"]
+                tar.addfile(info)
+                continue
+
+            raise ValueError(f"Unknown tar entry kind: {kind}")
+
+    return base64.b64encode(buf.getvalue()).decode("ascii")
+
+
+def test_extract_base64_tar_allows_safe_files(tmp_path, monkeypatch):
+    module = _load_terminalbench_module(monkeypatch)
+    archive = _build_tar_b64(
+        [
+            {"kind": "dir", "name": "nested"},
+            {"kind": "file", "name": "nested/hello.txt", "data": "hello"},
+        ]
+    )
+
+    target = tmp_path / "extract"
+    module._extract_base64_tar(archive, target)
+
+    assert (target / "nested" / "hello.txt").read_text(encoding="utf-8") == "hello"
+
+
+def test_extract_base64_tar_rejects_path_traversal(tmp_path, monkeypatch):
+    module = _load_terminalbench_module(monkeypatch)
+    archive = _build_tar_b64(
+        [
+            {"kind": "file", "name": "../escape.txt", "data": "owned"},
+        ]
+    )
+
+    target = tmp_path / "extract"
+    with pytest.raises(ValueError, match="Unsafe archive member path"):
+        module._extract_base64_tar(archive, target)
+
+    assert not (tmp_path / "escape.txt").exists()
+
+
+def test_extract_base64_tar_rejects_symlinks(tmp_path, monkeypatch):
+    module = _load_terminalbench_module(monkeypatch)
+    archive = _build_tar_b64(
+        [
+            {"kind": "symlink", "name": "link", "target": "../../escape.txt"},
+        ]
+    )
+
+    target = tmp_path / "extract"
+    with pytest.raises(ValueError, match="Unsupported archive member type"):
+        module._extract_base64_tar(archive, target)
+
+    assert not (target / "link").exists()