diff --git a/languages/python/custom/src/DetectUnsanitizedRglobPathTraversal.ql b/languages/python/custom/src/DetectUnsanitizedRglobPathTraversal.ql
new file mode 100644
index 0000000..346ad4e
--- /dev/null
+++ b/languages/python/custom/src/DetectUnsanitizedRglobPathTraversal.ql
@@ -0,0 +1,26 @@
+/**
+ * @name Uncontrolled data used in path expression (with pathlib sanitizer support)
+ * @description Accessing paths influenced by users can allow an attacker to access
+ *              unexpected resources. This query extends the standard py/path-injection
+ *              analysis to recognize `pathlib.Path.resolve()` as path normalization
+ *              and `pathlib.Path.is_relative_to()` as a safe access check.
+ * @kind path-problem
+ * @problem.severity warning
+ * @security-severity 7.5
+ * @precision high
+ * @id python/detect-unsanitized-rglob-path-traversal
+ * @tags security
+ *       external/cwe/cwe-022
+ */
+
+import python
+// Import custom sanitizer extensions; these extend Path::PathNormalization::Range
+// and Path::SafeAccessCheck::Range so the standard PathInjectionConfig picks them up.
+import PathInjectionSanitizers
+import semmle.python.security.dataflow.PathInjectionQuery
+import PathInjectionFlow::PathGraph
+
+from PathInjectionFlow::PathNode source, PathInjectionFlow::PathNode sink
+where PathInjectionFlow::flowPath(source, sink)
+select sink.getNode(), source, sink, "This path depends on a $@.", source.getNode(),
+  "user-provided value"
diff --git a/languages/python/custom/src/PathInjectionSanitizers.qll b/languages/python/custom/src/PathInjectionSanitizers.qll
new file mode 100644
index 0000000..71edf88
--- /dev/null
+++ b/languages/python/custom/src/PathInjectionSanitizers.qll
@@ -0,0 +1,73 @@
+/**
+ * Provides custom sanitizer extensions for the standard `py/path-injection` query.
+ *
+ * This module extends the CodeQL standard library's path injection analysis
+ * to recognize additional sanitization patterns:
+ *
+ * 1. `pathlib.Path.resolve()` as a path normalization step
+ * 2. `pathlib.Path.is_relative_to()` as a safe access check
+ *
+ * These extensions enable the standard query to understand that a pattern like:
+ * ```python
+ * resolved = job_dir.resolve()
+ * if not resolved.is_relative_to(JOBS_ROOT):
+ *     raise ValueError("path escapes root")
+ * matches = list(resolved.rglob("summary.csv"))
+ * ```
+ * properly sanitizes the path before use.
+ *
+ * NOTE: If contributing to the CodeQL standard library (re-bundling), these
+ * extensions should be added directly to `semmle/python/frameworks/Stdlib.qll`:
+ * - `PathlibResolveCall` alongside `OsPathRealpathCall` (around line 1065)
+ * - `IsRelativeToCall` alongside `StartswithCall` (around line 5090)
+ */
+
+private import python
+private import semmle.python.dataflow.new.DataFlow
+private import semmle.python.Concepts
+
+/**
+ * A call to `pathlib.Path.resolve()`, modeled as a path normalization step.
+ *
+ * `resolve()` makes the path absolute and resolves all symlinks, producing
+ * a canonical path. This is semantically equivalent to `os.path.realpath()`,
+ * which is already modeled as `Path::PathNormalization::Range` in the
+ * standard library.
+ *
+ * See https://docs.python.org/3/library/pathlib.html#pathlib.Path.resolve
+ */
+private class PathlibResolveCall extends Path::PathNormalization::Range, DataFlow::CallCfgNode {
+  /** The attribute read for the `.resolve` method access on a path object. */
+  DataFlow::AttrRead resolveMethodAccess;
+
+  PathlibResolveCall() {
+    resolveMethodAccess.getAttributeName() = "resolve" and
+    resolveMethodAccess.(DataFlow::LocalSourceNode).flowsTo(this.getFunction())
+  }
+
+  override DataFlow::Node getPathArg() { result = resolveMethodAccess.getObject() }
+}
+
+/**
+ * A call to `pathlib.PurePath.is_relative_to()`, modeled as a safe access check.
+ *
+ * `is_relative_to(other)` returns `True` if the path is relative to `other`,
+ * which is commonly used as a path confinement check to verify that a resolved
+ * path remains within an expected directory. This is semantically similar to
+ * `str.startswith()`, which is already modeled as `Path::SafeAccessCheck::Range`
+ * in the standard library.
+ *
+ * See https://docs.python.org/3/library/pathlib.html#pathlib.PurePath.is_relative_to
+ */
+private class IsRelativeToCall extends Path::SafeAccessCheck::Range {
+  IsRelativeToCall() {
+    this.(CallNode).getFunction().(AttrNode).getName() = "is_relative_to"
+  }
+
+  override predicate checks(ControlFlowNode node, boolean branch) {
+    // When is_relative_to() returns True (branch = true), the path is confirmed
+    // to be confined within the expected directory, making it safe to access.
+    node = this.(CallNode).getFunction().(AttrNode).getObject() and
+    branch = true
+  }
+}
diff --git a/languages/python/custom/test/DetectUnsanitizedRglobPathTraversal/DetectUnsanitizedRglobPathTraversal.expected b/languages/python/custom/test/DetectUnsanitizedRglobPathTraversal/DetectUnsanitizedRglobPathTraversal.expected
new file mode 100644
index 0000000..1b83bc8
--- /dev/null
+++ b/languages/python/custom/test/DetectUnsanitizedRglobPathTraversal/DetectUnsanitizedRglobPathTraversal.expected
@@ -0,0 +1,94 @@
+edges
+| test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for request | provenance |  |
+| test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for request | test_rglob_sanitization.py:14:14:14:20 | ControlFlowNode for request | provenance |  |
+| test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for request | test_rglob_sanitization.py:23:14:23:20 | ControlFlowNode for request | provenance |  |
+| test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for request | test_rglob_sanitization.py:36:14:36:20 | ControlFlowNode for request | provenance |  |
+| test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for request | test_rglob_sanitization.py:46:14:46:20 | ControlFlowNode for request | provenance |  |
+| test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for request | test_rglob_sanitization.py:57:14:57:20 | ControlFlowNode for request | provenance |  |
+| test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for request | test_rglob_sanitization.py:70:14:70:20 | ControlFlowNode for request | provenance |  |
+| test_rglob_sanitization.py:14:5:14:10 | ControlFlowNode for job_id | test_rglob_sanitization.py:15:5:15:11 | ControlFlowNode for job_dir | provenance | AdditionalTaintStep |
+| test_rglob_sanitization.py:14:14:14:20 | ControlFlowNode for request | test_rglob_sanitization.py:14:14:14:25 | ControlFlowNode for Attribute | provenance | AdditionalTaintStep |
+| test_rglob_sanitization.py:14:14:14:25 | ControlFlowNode for Attribute | test_rglob_sanitization.py:14:14:14:43 | ControlFlowNode for Attribute() | provenance | dict.get |
+| test_rglob_sanitization.py:14:14:14:43 | ControlFlowNode for Attribute() | test_rglob_sanitization.py:14:5:14:10 | ControlFlowNode for job_id | provenance |  |
+| test_rglob_sanitization.py:15:5:15:11 | ControlFlowNode for job_dir | test_rglob_sanitization.py:16:20:16:26 | ControlFlowNode for job_dir | provenance |  |
+| test_rglob_sanitization.py:23:5:23:10 | ControlFlowNode for job_id | test_rglob_sanitization.py:24:5:24:11 | ControlFlowNode for job_dir | provenance | AdditionalTaintStep |
+| test_rglob_sanitization.py:23:14:23:20 | ControlFlowNode for request | test_rglob_sanitization.py:23:14:23:25 | ControlFlowNode for Attribute | provenance | AdditionalTaintStep |
+| test_rglob_sanitization.py:23:14:23:25 | ControlFlowNode for Attribute | test_rglob_sanitization.py:23:14:23:43 | ControlFlowNode for Attribute() | provenance | dict.get |
+| test_rglob_sanitization.py:23:14:23:43 | ControlFlowNode for Attribute() | test_rglob_sanitization.py:23:5:23:10 | ControlFlowNode for job_id | provenance |  |
+| test_rglob_sanitization.py:24:5:24:11 | ControlFlowNode for job_dir | test_rglob_sanitization.py:25:16:25:22 | ControlFlowNode for job_dir | provenance |  |
+| test_rglob_sanitization.py:36:5:36:10 | ControlFlowNode for job_id | test_rglob_sanitization.py:37:5:37:11 | ControlFlowNode for job_dir | provenance | AdditionalTaintStep |
+| test_rglob_sanitization.py:36:14:36:20 | ControlFlowNode for request | test_rglob_sanitization.py:36:14:36:25 | ControlFlowNode for Attribute | provenance | AdditionalTaintStep |
+| test_rglob_sanitization.py:36:14:36:25 | ControlFlowNode for Attribute | test_rglob_sanitization.py:36:14:36:43 | ControlFlowNode for Attribute() | provenance | dict.get |
+| test_rglob_sanitization.py:36:14:36:43 | ControlFlowNode for Attribute() | test_rglob_sanitization.py:36:5:36:10 | ControlFlowNode for job_id | provenance |  |
+| test_rglob_sanitization.py:37:5:37:11 | ControlFlowNode for job_dir | test_rglob_sanitization.py:38:16:38:22 | ControlFlowNode for job_dir | provenance |  |
+| test_rglob_sanitization.py:37:5:37:11 | ControlFlowNode for job_dir | test_rglob_sanitization.py:38:16:38:22 | ControlFlowNode for job_dir | provenance |  |
+| test_rglob_sanitization.py:38:5:38:12 | ControlFlowNode for resolved | test_rglob_sanitization.py:39:20:39:27 | ControlFlowNode for resolved | provenance |  |
+| test_rglob_sanitization.py:38:16:38:22 | ControlFlowNode for job_dir | test_rglob_sanitization.py:38:16:38:32 | ControlFlowNode for Attribute() | provenance | Config |
+| test_rglob_sanitization.py:38:16:38:32 | ControlFlowNode for Attribute() | test_rglob_sanitization.py:38:5:38:12 | ControlFlowNode for resolved | provenance |  |
+| test_rglob_sanitization.py:46:5:46:10 | ControlFlowNode for job_id | test_rglob_sanitization.py:47:5:47:11 | ControlFlowNode for job_dir | provenance | AdditionalTaintStep |
+| test_rglob_sanitization.py:46:14:46:20 | ControlFlowNode for request | test_rglob_sanitization.py:46:14:46:25 | ControlFlowNode for Attribute | provenance | AdditionalTaintStep |
+| test_rglob_sanitization.py:46:14:46:25 | ControlFlowNode for Attribute | test_rglob_sanitization.py:46:14:46:43 | ControlFlowNode for Attribute() | provenance | dict.get |
+| test_rglob_sanitization.py:46:14:46:43 | ControlFlowNode for Attribute() | test_rglob_sanitization.py:46:5:46:10 | ControlFlowNode for job_id | provenance |  |
+| test_rglob_sanitization.py:47:5:47:11 | ControlFlowNode for job_dir | test_rglob_sanitization.py:50:20:50:26 | ControlFlowNode for job_dir | provenance |  |
+| test_rglob_sanitization.py:57:5:57:10 | ControlFlowNode for job_id | test_rglob_sanitization.py:58:5:58:11 | ControlFlowNode for job_dir | provenance | AdditionalTaintStep |
+| test_rglob_sanitization.py:57:14:57:20 | ControlFlowNode for request | test_rglob_sanitization.py:57:14:57:25 | ControlFlowNode for Attribute | provenance | AdditionalTaintStep |
+| test_rglob_sanitization.py:57:14:57:25 | ControlFlowNode for Attribute | test_rglob_sanitization.py:57:14:57:43 | ControlFlowNode for Attribute() | provenance | dict.get |
+| test_rglob_sanitization.py:57:14:57:43 | ControlFlowNode for Attribute() | test_rglob_sanitization.py:57:5:57:10 | ControlFlowNode for job_id | provenance |  |
+| test_rglob_sanitization.py:58:5:58:11 | ControlFlowNode for job_dir | test_rglob_sanitization.py:59:16:59:22 | ControlFlowNode for job_dir | provenance |  |
+| test_rglob_sanitization.py:70:5:70:10 | ControlFlowNode for job_id | test_rglob_sanitization.py:71:5:71:11 | ControlFlowNode for job_dir | provenance | AdditionalTaintStep |
+| test_rglob_sanitization.py:70:14:70:20 | ControlFlowNode for request | test_rglob_sanitization.py:70:14:70:25 | ControlFlowNode for Attribute | provenance | AdditionalTaintStep |
+| test_rglob_sanitization.py:70:14:70:25 | ControlFlowNode for Attribute | test_rglob_sanitization.py:70:14:70:43 | ControlFlowNode for Attribute() | provenance | dict.get |
+| test_rglob_sanitization.py:70:14:70:43 | ControlFlowNode for Attribute() | test_rglob_sanitization.py:70:5:70:10 | ControlFlowNode for job_id | provenance |  |
+| test_rglob_sanitization.py:71:5:71:11 | ControlFlowNode for job_dir | test_rglob_sanitization.py:72:9:72:15 | ControlFlowNode for job_dir | provenance |  |
+nodes
+| test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | semmle.label | ControlFlowNode for ImportMember |
+| test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for request | semmle.label | ControlFlowNode for request |
+| test_rglob_sanitization.py:14:5:14:10 | ControlFlowNode for job_id | semmle.label | ControlFlowNode for job_id |
+| test_rglob_sanitization.py:14:14:14:20 | ControlFlowNode for request | semmle.label | ControlFlowNode for request |
+| test_rglob_sanitization.py:14:14:14:25 | ControlFlowNode for Attribute | semmle.label | ControlFlowNode for Attribute |
+| test_rglob_sanitization.py:14:14:14:43 | ControlFlowNode for Attribute() | semmle.label | ControlFlowNode for Attribute() |
+| test_rglob_sanitization.py:15:5:15:11 | ControlFlowNode for job_dir | semmle.label | ControlFlowNode for job_dir |
+| test_rglob_sanitization.py:16:20:16:26 | ControlFlowNode for job_dir | semmle.label | ControlFlowNode for job_dir |
+| test_rglob_sanitization.py:23:5:23:10 | ControlFlowNode for job_id | semmle.label | ControlFlowNode for job_id |
+| test_rglob_sanitization.py:23:14:23:20 | ControlFlowNode for request | semmle.label | ControlFlowNode for request |
+| test_rglob_sanitization.py:23:14:23:25 | ControlFlowNode for Attribute | semmle.label | ControlFlowNode for Attribute |
+| test_rglob_sanitization.py:23:14:23:43 | ControlFlowNode for Attribute() | semmle.label | ControlFlowNode for Attribute() |
+| test_rglob_sanitization.py:24:5:24:11 | ControlFlowNode for job_dir | semmle.label | ControlFlowNode for job_dir |
+| test_rglob_sanitization.py:25:16:25:22 | ControlFlowNode for job_dir | semmle.label | ControlFlowNode for job_dir |
+| test_rglob_sanitization.py:36:5:36:10 | ControlFlowNode for job_id | semmle.label | ControlFlowNode for job_id |
+| test_rglob_sanitization.py:36:14:36:20 | ControlFlowNode for request | semmle.label | ControlFlowNode for request |
+| test_rglob_sanitization.py:36:14:36:25 | ControlFlowNode for Attribute | semmle.label | ControlFlowNode for Attribute |
+| test_rglob_sanitization.py:36:14:36:43 | ControlFlowNode for Attribute() | semmle.label | ControlFlowNode for Attribute() |
+| test_rglob_sanitization.py:37:5:37:11 | ControlFlowNode for job_dir | semmle.label | ControlFlowNode for job_dir |
+| test_rglob_sanitization.py:38:5:38:12 | ControlFlowNode for resolved | semmle.label | ControlFlowNode for resolved |
+| test_rglob_sanitization.py:38:16:38:22 | ControlFlowNode for job_dir | semmle.label | ControlFlowNode for job_dir |
+| test_rglob_sanitization.py:38:16:38:22 | ControlFlowNode for job_dir | semmle.label | ControlFlowNode for job_dir |
+| test_rglob_sanitization.py:38:16:38:32 | ControlFlowNode for Attribute() | semmle.label | ControlFlowNode for Attribute() |
+| test_rglob_sanitization.py:39:20:39:27 | ControlFlowNode for resolved | semmle.label | ControlFlowNode for resolved |
+| test_rglob_sanitization.py:46:5:46:10 | ControlFlowNode for job_id | semmle.label | ControlFlowNode for job_id |
+| test_rglob_sanitization.py:46:14:46:20 | ControlFlowNode for request | semmle.label | ControlFlowNode for request |
+| test_rglob_sanitization.py:46:14:46:25 | ControlFlowNode for Attribute | semmle.label | ControlFlowNode for Attribute |
+| test_rglob_sanitization.py:46:14:46:43 | ControlFlowNode for Attribute() | semmle.label | ControlFlowNode for Attribute() |
+| test_rglob_sanitization.py:47:5:47:11 | ControlFlowNode for job_dir | semmle.label | ControlFlowNode for job_dir |
+| test_rglob_sanitization.py:50:20:50:26 | ControlFlowNode for job_dir | semmle.label | ControlFlowNode for job_dir |
+| test_rglob_sanitization.py:57:5:57:10 | ControlFlowNode for job_id | semmle.label | ControlFlowNode for job_id |
+| test_rglob_sanitization.py:57:14:57:20 | ControlFlowNode for request | semmle.label | ControlFlowNode for request |
+| test_rglob_sanitization.py:57:14:57:25 | ControlFlowNode for Attribute | semmle.label | ControlFlowNode for Attribute |
+| test_rglob_sanitization.py:57:14:57:43 | ControlFlowNode for Attribute() | semmle.label | ControlFlowNode for Attribute() |
+| test_rglob_sanitization.py:58:5:58:11 | ControlFlowNode for job_dir | semmle.label | ControlFlowNode for job_dir |
+| test_rglob_sanitization.py:59:16:59:22 | ControlFlowNode for job_dir | semmle.label | ControlFlowNode for job_dir |
+| test_rglob_sanitization.py:70:5:70:10 | ControlFlowNode for job_id | semmle.label | ControlFlowNode for job_id |
+| test_rglob_sanitization.py:70:14:70:20 | ControlFlowNode for request | semmle.label | ControlFlowNode for request |
+| test_rglob_sanitization.py:70:14:70:25 | ControlFlowNode for Attribute | semmle.label | ControlFlowNode for Attribute |
+| test_rglob_sanitization.py:70:14:70:43 | ControlFlowNode for Attribute() | semmle.label | ControlFlowNode for Attribute() |
+| test_rglob_sanitization.py:71:5:71:11 | ControlFlowNode for job_dir | semmle.label | ControlFlowNode for job_dir |
+| test_rglob_sanitization.py:72:9:72:15 | ControlFlowNode for job_dir | semmle.label | ControlFlowNode for job_dir |
+subpaths
+#select
+| test_rglob_sanitization.py:16:20:16:26 | ControlFlowNode for job_dir | test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | test_rglob_sanitization.py:16:20:16:26 | ControlFlowNode for job_dir | This path depends on a $@. | test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | user-provided value |
+| test_rglob_sanitization.py:25:16:25:22 | ControlFlowNode for job_dir | test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | test_rglob_sanitization.py:25:16:25:22 | ControlFlowNode for job_dir | This path depends on a $@. | test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | user-provided value |
+| test_rglob_sanitization.py:38:16:38:22 | ControlFlowNode for job_dir | test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | test_rglob_sanitization.py:38:16:38:22 | ControlFlowNode for job_dir | This path depends on a $@. | test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | user-provided value |
+| test_rglob_sanitization.py:39:20:39:27 | ControlFlowNode for resolved | test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | test_rglob_sanitization.py:39:20:39:27 | ControlFlowNode for resolved | This path depends on a $@. | test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | user-provided value |
+| test_rglob_sanitization.py:50:20:50:26 | ControlFlowNode for job_dir | test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | test_rglob_sanitization.py:50:20:50:26 | ControlFlowNode for job_dir | This path depends on a $@. | test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | user-provided value |
+| test_rglob_sanitization.py:59:16:59:22 | ControlFlowNode for job_dir | test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | test_rglob_sanitization.py:59:16:59:22 | ControlFlowNode for job_dir | This path depends on a $@. | test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | user-provided value |
+| test_rglob_sanitization.py:72:9:72:15 | ControlFlowNode for job_dir | test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | test_rglob_sanitization.py:72:9:72:15 | ControlFlowNode for job_dir | This path depends on a $@. | test_rglob_sanitization.py:4:26:4:32 | ControlFlowNode for ImportMember | user-provided value |
diff --git a/languages/python/custom/test/DetectUnsanitizedRglobPathTraversal/DetectUnsanitizedRglobPathTraversal.qlref b/languages/python/custom/test/DetectUnsanitizedRglobPathTraversal/DetectUnsanitizedRglobPathTraversal.qlref
new file mode 100644
index 0000000..70bac22
--- /dev/null
+++ b/languages/python/custom/test/DetectUnsanitizedRglobPathTraversal/DetectUnsanitizedRglobPathTraversal.qlref
@@ -0,0 +1 @@
+DetectUnsanitizedRglobPathTraversal.ql
diff --git a/languages/python/custom/test/DetectUnsanitizedRglobPathTraversal/test_rglob_sanitization.py b/languages/python/custom/test/DetectUnsanitizedRglobPathTraversal/test_rglob_sanitization.py
new file mode 100644
index 0000000..028c8c3
--- /dev/null
+++ b/languages/python/custom/test/DetectUnsanitizedRglobPathTraversal/test_rglob_sanitization.py
@@ -0,0 +1,85 @@
+import os
+import pathlib
+
+from flask import Flask, request
+
+app = Flask(__name__)
+
+JOBS_ROOT = pathlib.Path("/data/jobs")
+
+
+@app.route("/unsanitized")
+def unsanitized_rglob():
+    """Detected: no sanitization at all."""
+    job_id = request.args.get("job_id", "")
+    job_dir = JOBS_ROOT / job_id
+    matches = list(job_dir.rglob("summary.csv"))  # Alert: unsanitized path
+    return str(matches)
+
+
+@app.route("/sanitized_resolve_and_is_relative_to")
+def sanitized_rglob():
+    """resolve() + is_relative_to() properly sanitizes the rglob call."""
+    job_id = request.args.get("job_id", "")
+    job_dir = JOBS_ROOT / job_id
+    resolved = job_dir.resolve()  # Alert on resolve() itself (it is a FileSystemAccess in stdlib)
+    if not resolved.is_relative_to(JOBS_ROOT):
+        raise ValueError("path escapes root")
+    # NOT detected: resolve() normalized the path, is_relative_to() confirmed confinement
+    matches = list(resolved.rglob("summary.csv"))
+    return str(matches)
+
+
+@app.route("/resolve_only")
+def resolve_only_rglob():
+    """Detected: resolve() without is_relative_to() is insufficient."""
+    job_id = request.args.get("job_id", "")
+    job_dir = JOBS_ROOT / job_id
+    resolved = job_dir.resolve()  # Alert on resolve() itself (FileSystemAccess)
+    matches = list(resolved.rglob("summary.csv"))  # Alert: normalized but not checked
+    return str(matches)
+
+
+@app.route("/is_relative_to_without_resolve")
+def is_relative_to_without_resolve():
+    """Detected: is_relative_to() without resolve() first is bypassable."""
+    job_id = request.args.get("job_id", "")
+    job_dir = JOBS_ROOT / job_id
+    if not job_dir.is_relative_to(JOBS_ROOT):
+        raise ValueError("path escapes root")
+    matches = list(job_dir.rglob("summary.csv"))  # Alert: checked but not normalized
+    return str(matches)
+
+
+@app.route("/sanitized_open")
+def sanitized_open():
+    """resolve() + is_relative_to() properly sanitizes the open() call."""
+    job_id = request.args.get("job_id", "")
+    job_dir = JOBS_ROOT / job_id
+    resolved = job_dir.resolve()  # Alert on resolve() itself (FileSystemAccess)
+    if not resolved.is_relative_to(JOBS_ROOT):
+        raise ValueError("path escapes root")
+    # NOT detected: properly sanitized
+    f = resolved.open()
+    return f.read()
+
+
+@app.route("/unsanitized_open")
+def unsanitized_open():
+    """Detected: unsanitized open()."""
+    job_id = request.args.get("job_id", "")
+    job_dir = JOBS_ROOT / job_id
+    f = job_dir.open()  # Alert: unsanitized path
+    return f.read()
+
+
+@app.route("/realpath_startswith")
+def realpath_startswith():
+    """Not detected: os.path.realpath + startswith (existing sanitizer)."""
+    job_id = request.args.get("job_id", "")
+    path = os.path.join("/data/jobs", job_id)
+    npath = os.path.realpath(path)
+    if npath.startswith("/data/jobs"):
+        f = open(npath)  # Not detected: properly sanitized by existing sanitizer
+        return f.read()
+    return "error"