Require approval for path-qualified safe commands

codex-rs/core/src/exec_policy_tests.rs

@@ -1178,6 +1178,27 @@ fn git_branch_requires_approval_for_untrusted_projects() {
     );
 }
 
+#[test]
+fn path_qualified_safe_basename_requires_approval_for_untrusted_projects() {
+    let executable = if cfg!(windows) { r".\cat.exe" } else { "./cat" };
+    let command = vec![executable.to_string(), "Cargo.toml".to_string()];
+
+    assert_eq!(
+        Decision::Prompt,
+        render_decision_for_unmatched_command(
+            &command,
+            UnmatchedCommandContext {
+                approval_policy: AskForApproval::UnlessTrusted,
+                permission_profile: &PermissionProfile::workspace_write(),
+                windows_sandbox_level: WindowsSandboxLevel::Disabled,
+                sandbox_permissions: SandboxPermissions::UseDefault,
+                used_complex_parsing: false,
+                command_origin: ExecPolicyCommandOrigin::Generic,
+            },
+        )
+    );
+}
+
 #[test]
 fn managed_cwd_write_profile_has_filesystem_restrictions() {
     let file_system_sandbox_policy = FileSystemSandboxPolicy::restricted(vec![

codex-rs/shell-command/src/command_safety/is_safe_command.rs

@@ -64,6 +64,12 @@ fn is_safe_to_call_with_exec(command: &[String]) -> bool {
     let Some(cmd0) = command.first().map(String::as_str) else {
         return false;
     };
+    if std::path::Path::new(cmd0).components().count() != 1 {
+        // A workspace executable can impersonate an allowlisted utility by
+        // reusing its basename. Only bare names resolved through the trusted
+        // process PATH are eligible for generic safe-command classification.
+        return false;
+    }
 
     match executable_name_lookup_key(cmd0).as_deref() {
         Some(cmd) if cfg!(target_os = "linux") && matches!(cmd, "numfmt" | "tac") => true,
@@ -250,6 +256,35 @@ mod tests {
         }
     }
 
+    #[test]
+    fn path_qualified_safe_command_names_require_approval() {
+        let absolute_cat = if cfg!(windows) {
+            r"C:\workspace\cat.exe"
+        } else {
+            "/tmp/workspace/cat"
+        };
+        let parent_relative_cat = if cfg!(windows) {
+            r"..\cat.exe"
+        } else {
+            "../cat"
+        };
+
+        for args in [
+            vec_str(&["./cat", "Cargo.toml"]),
+            vec_str(&[parent_relative_cat, "Cargo.toml"]),
+            vec_str(&[absolute_cat, "Cargo.toml"]),
+            vec_str(&["bash", "-lc", "./cat Cargo.toml"]),
+        ] {
+            assert!(
+                !is_known_safe_command(&args),
+                "expected path-qualified executable {args:?} to require approval",
+            );
+        }
+
+        let bare_cat = if cfg!(windows) { "cat.exe" } else { "cat" };
+        assert!(is_known_safe_command(&vec_str(&[bare_cat, "Cargo.toml"])));
+    }
+
     #[test]
     fn git_commands_require_approval() {
         for args in [