diff --git a/src/uu/env/src/env.rs b/src/uu/env/src/env.rs
index 4d99e3302..ec9360ad4 100644
--- a/src/uu/env/src/env.rs
+++ b/src/uu/env/src/env.rs
@@ -163,7 +163,9 @@ fn load_config_file(opts: &mut Options) -> UResult<()> {
         for (_, prop) in &conf {
             // ignore all INI section lines (treat them as comments)
             for (key, value) in prop {
-                env::set_var(key, value);
+                unsafe {
+                    env::set_var(key, value);
+                }
             }
         }
     }
@@ -559,7 +561,9 @@ fn apply_removal_of_all_env_vars(opts: &Options<'_>) {
     // remove all env vars if told to ignore presets
     if opts.ignore_env {
         for (ref name, _) in env::vars_os() {
-            env::remove_var(name);
+            unsafe {
+                env::remove_var(name);
+            }
         }
     }
 }
@@ -634,8 +638,9 @@ fn apply_unset_env_vars(opts: &Options<'_>) -> Result<(), Box<dyn UError>> {
                 format!("cannot unset {}: Invalid argument", name.quote()),
             ));
         }
-
-        env::remove_var(name);
+        unsafe {
+            env::remove_var(name);
+        }
     }
     Ok(())
 }
@@ -692,7 +697,9 @@ fn apply_specified_env_vars(opts: &Options<'_>) {
             show_warning!("no name specified for value {}", val.quote());
             continue;
         }
-        env::set_var(name, val);
+        unsafe {
+            env::set_var(name, val);
+        }
     }
 }
 
diff --git a/src/uu/sort/src/sort.rs b/src/uu/sort/src/sort.rs
index 645d32023..c1247aa00 100644
--- a/src/uu/sort/src/sort.rs
+++ b/src/uu/sort/src/sort.rs
@@ -1111,7 +1111,9 @@ pub fn uumain(args: impl uucore::Args) -> UResult<()> {
             .get_one::<String>(options::PARALLEL)
             .map(String::from)
             .unwrap_or_else(|| "0".to_string());
-        env::set_var("RAYON_NUM_THREADS", &settings.threads);
+        unsafe {
+            env::set_var("RAYON_NUM_THREADS", &settings.threads);
+        }
     }
 
     settings.buffer_size =
diff --git a/src/uu/split/src/platform/unix.rs b/src/uu/split/src/platform/unix.rs
index 1e29739e2..451abef92 100644
--- a/src/uu/split/src/platform/unix.rs
+++ b/src/uu/split/src/platform/unix.rs
@@ -49,7 +49,9 @@ impl WithEnvVarSet {
     /// Save previous value assigned to key, set key=value
     fn new(key: &str, value: &str) -> Self {
         let previous_env_value = env::var(key);
-        env::set_var(key, value);
+        unsafe {
+            env::set_var(key, value);
+        }
         Self {
             _previous_var_key: String::from(key),
             _previous_var_value: previous_env_value,
@@ -61,9 +63,13 @@ impl Drop for WithEnvVarSet {
     /// Restore previous value now that this is being dropped by context
     fn drop(&mut self) {
         if let Ok(ref prev_value) = self._previous_var_value {
-            env::set_var(&self._previous_var_key, prev_value);
+            unsafe {
+                env::set_var(&self._previous_var_key, prev_value);
+            }
         } else {
-            env::remove_var(&self._previous_var_key);
+            unsafe {
+                env::remove_var(&self._previous_var_key);
+            }
         }
     }
 }
diff --git a/src/uu/stdbuf/src/libstdbuf/src/libstdbuf.rs b/src/uu/stdbuf/src/libstdbuf/src/libstdbuf.rs
index 375ae5f2d..f365fe596 100644
--- a/src/uu/stdbuf/src/libstdbuf/src/libstdbuf.rs
+++ b/src/uu/stdbuf/src/libstdbuf/src/libstdbuf.rs
@@ -64,7 +64,7 @@ fn set_buffer(stream: *mut FILE, value: &str) {
 
 /// # Safety
 /// ToDO ... (safety note)
-#[no_mangle]
+#[unsafe(no_mangle)]
 pub unsafe extern "C" fn __stdbuf() {
     if let Ok(val) = env::var("_STDBUF_E") {
         set_buffer(__stdbuf_get_stderr(), &val);
diff --git a/tests/by-util/test_dircolors.rs b/tests/by-util/test_dircolors.rs
index 53f79f5ae..e5fba5eb5 100644
--- a/tests/by-util/test_dircolors.rs
+++ b/tests/by-util/test_dircolors.rs
@@ -16,25 +16,43 @@ fn test_invalid_arg() {
 fn test_shell_syntax() {
     use std::env;
     let last = env::var("SHELL");
-    env::set_var("SHELL", "/path/csh");
+    unsafe {
+        env::set_var("SHELL", "/path/csh");
+    }
     assert_eq!(OutputFmt::CShell, guess_syntax());
-    env::set_var("SHELL", "csh");
+    unsafe {
+        env::set_var("SHELL", "csh");
+    }
     assert_eq!(OutputFmt::CShell, guess_syntax());
-    env::set_var("SHELL", "/path/bash");
+    unsafe {
+        env::set_var("SHELL", "/path/bash");
+    }
     assert_eq!(OutputFmt::Shell, guess_syntax());
-    env::set_var("SHELL", "bash");
+    unsafe {
+        env::set_var("SHELL", "bash");
+    }
     assert_eq!(OutputFmt::Shell, guess_syntax());
-    env::set_var("SHELL", "/asd/bar");
+    unsafe {
+        env::set_var("SHELL", "/asd/bar");
+    }
     assert_eq!(OutputFmt::Shell, guess_syntax());
-    env::set_var("SHELL", "foo");
+    unsafe {
+        env::set_var("SHELL", "foo");
+    }
     assert_eq!(OutputFmt::Shell, guess_syntax());
-    env::set_var("SHELL", "");
+    unsafe {
+        env::set_var("SHELL", "");
+    }
     assert_eq!(OutputFmt::Unknown, guess_syntax());
-    env::remove_var("SHELL");
+    unsafe {
+        env::remove_var("SHELL");
+    }
     assert_eq!(OutputFmt::Unknown, guess_syntax());
 
     if let Ok(s) = last {
-        env::set_var("SHELL", s);
+        unsafe {
+            env::set_var("SHELL", s);
+        }
     }
 }
 
diff --git a/tests/by-util/test_split.rs b/tests/by-util/test_split.rs
index c21299eaa..494505715 100644
--- a/tests/by-util/test_split.rs
+++ b/tests/by-util/test_split.rs
@@ -324,7 +324,9 @@ fn test_filter_with_env_var_set() {
     RandomFile::new(&at, name).add_lines(n_lines);
 
     let env_var_value = "some-value";
-    env::set_var("FILE", env_var_value);
+    unsafe {
+        env::set_var("FILE", env_var_value);
+    }
     ucmd.args(&[format!("--filter={}", "cat > $FILE").as_str(), name])
         .succeeds();