diff --git a/ext/posix/posix.c b/ext/posix/posix.c
index b7acf8c751270..81346a2b266e7 100644
--- a/ext/posix/posix.c
+++ b/ext/posix/posix.c
@@ -621,6 +621,14 @@ PHP_FUNCTION(posix_mkfifo)
 		RETURN_FALSE;
 	}
 
+	if (mode < 0 || (mode & ~07777)) {
+		zend_argument_value_error(
+			2,
+			"must be between 0 and 07777"
+		);
+		RETURN_THROWS();
+	}
+
 	result = mkfifo(ZSTR_VAL(path), mode);
 	if (result < 0) {
 		POSIX_G(last_error) = errno;
diff --git a/ext/posix/tests/posix_mkfifo_invalid_mode.phpt b/ext/posix/tests/posix_mkfifo_invalid_mode.phpt
new file mode 100644
index 0000000000000..5aa6c68a515f1
--- /dev/null
+++ b/ext/posix/tests/posix_mkfifo_invalid_mode.phpt
@@ -0,0 +1,36 @@
+--TEST--
+posix_mkfifo(): invalid mode argument
+--SKIPIF--
+<?php
+if (!function_exists("posix_mkfifo")) {
+    die("skip no posix_mkfifo()");
+}
+?>
+--FILE--
+<?php
+
+// Negative mode
+try {
+    posix_mkfifo(__DIR__ . "/testfifo1", -1);
+} catch (ValueError $e) {
+    echo $e->getMessage(), "\n";
+}
+
+// Too large mode
+try {
+    posix_mkfifo(__DIR__ . "/testfifo2", 010000); // > 07777
+} catch (ValueError $e) {
+    echo $e->getMessage(), "\n";
+}
+
+// Garbage bits
+try {
+    posix_mkfifo(__DIR__ . "/testfifo3", 020000); // S_IFCHR bit
+} catch (ValueError $e) {
+    echo $e->getMessage(), "\n";
+}
+?>
+--EXPECTF--
+posix_mkfifo(): Argument #2 ($permissions) must be between 0 and 07777
+posix_mkfifo(): Argument #2 ($permissions) must be between 0 and 07777
+posix_mkfifo(): Argument #2 ($permissions) must be between 0 and 07777