From e9d99a66834c5aeb79497af354e4ddd3db6454ab Mon Sep 17 00:00:00 2001
From: terrafrost <terrafrost@php.net>
Date: Sun, 26 May 2019 11:14:58 -0500
Subject: [PATCH 1/2] Tests/BigInteger: add unit test for 0 loaded as base-10

---
 tests/Unit/Math/BigInteger/TestCase.php | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/tests/Unit/Math/BigInteger/TestCase.php b/tests/Unit/Math/BigInteger/TestCase.php
index e7f7bbeb..821e4280 100644
--- a/tests/Unit/Math/BigInteger/TestCase.php
+++ b/tests/Unit/Math/BigInteger/TestCase.php
@@ -406,4 +406,10 @@ abstract class Unit_Math_BigInteger_TestCase extends PhpseclibTestCase
         $temp = $this->getInstance(48);
         $this->assertSame($temp->toHex(true), '30');
     }
+
+    public function testZeroBase10()
+    {
+        $temp = $this->getInstance('00');
+        $this->assertSame($temp->toString(), '0');
+    }
 }

From 9c67616f1eba5ed0f7eb128095542811b0f42e3b Mon Sep 17 00:00:00 2001
From: terrafrost <terrafrost@php.net>
Date: Sun, 26 May 2019 11:41:03 -0500
Subject: [PATCH 2/2] BigInteger: new BigInteger('00') caused issues with GMP

---
 phpseclib/Math/BigInteger.php | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/phpseclib/Math/BigInteger.php b/phpseclib/Math/BigInteger.php
index 9082ad5f..da79b031 100644
--- a/phpseclib/Math/BigInteger.php
+++ b/phpseclib/Math/BigInteger.php
@@ -441,6 +441,9 @@ class Math_BigInteger
                 // (?<=^|-)0*: find any 0's that are preceded by the start of the string or by a - (ie. octals)
                 // [^-0-9].*: find any non-numeric characters and then any characters that follow that
                 $x = preg_replace('#(?<!^)(?:-).*|(?<=^|-)0*|[^-0-9].*#', '', $x);
+                if (!strlen($x)) {
+                    $x = '0';
+                }
 
                 switch (MATH_BIGINTEGER_MODE) {
                     case MATH_BIGINTEGER_MODE_GMP: