diff --git a/core/fpdfapi/parser/cpdf_security_handler.cpp b/core/fpdfapi/parser/cpdf_security_handler.cpp
index 0c8eadd..0c98bfb 100644
--- a/core/fpdfapi/parser/cpdf_security_handler.cpp
+++ b/core/fpdfapi/parser/cpdf_security_handler.cpp
@@ -18,7 +18,7 @@
 #include "core/fpdfapi/parser/cpdf_dictionary.h"
 #include "core/fpdfapi/parser/cpdf_object.h"
 #include "core/fpdfapi/parser/cpdf_string.h"
-#include "core/fxcrt/fx_extension.h"
+#include "core/fxcrt/fx_random.h"
 #include "third_party/base/ptr_util.h"
 
 namespace {
@@ -521,17 +521,17 @@
 ByteString CPDF_SecurityHandler::GetEncodedPassword(
     ByteStringView password) const {
   switch (m_PasswordEncodingConversion) {
-    case CPDF_SecurityHandler::kNone:
+    case kNone:
       // Do nothing.
       return ByteString(password);
-    case CPDF_SecurityHandler::kLatin1ToUtf8:
+    case kLatin1ToUtf8:
       return WideString::FromLatin1(password).ToUTF8();
-    case CPDF_SecurityHandler::kUtf8toLatin1:
+    case kUtf8toLatin1:
       return WideString::FromUTF8(password).ToLatin1();
     default:
       NOTREACHED();
       return ByteString(password);
-  };
+  }
 }
 
 void CPDF_SecurityHandler::OnCreateInternal(CPDF_Dictionary* pEncryptDict,
@@ -551,12 +551,12 @@
     owner_password_copy = user_password;
 
   if (m_Revision >= 5) {
-    int t = static_cast<int>(FXSYS_time(nullptr));
+    uint32_t random[4];
+    FX_Random_GenerateMT(random, FX_ArraySize(random));
     CRYPT_sha2_context sha;
     CRYPT_SHA256Start(&sha);
-    CRYPT_SHA256Update(&sha, (uint8_t*)&t, sizeof t);
-    CRYPT_SHA256Update(&sha, m_EncryptKey, 32);
-    CRYPT_SHA256Update(&sha, (uint8_t*)"there", 5);
+    CRYPT_SHA256Update(&sha, reinterpret_cast<uint8_t*>(random),
+                       sizeof(random));
     CRYPT_SHA256Finish(&sha, m_EncryptKey);
     AES256_SetPassword(pEncryptDict, user_password, false, m_EncryptKey);
     if (bDefault)
@@ -716,6 +716,11 @@
   buf[10] = 'd';
   buf[11] = 'b';
 
+  // In ISO 32000 Supplement for ExtensionLevel 3, Algorithm 3.10 says bytes 12
+  // to 15 should be random data.
+  uint32_t* buf_random = reinterpret_cast<uint32_t*>(&buf[12]);
+  FX_Random_GenerateMT(buf_random, 1);
+
   CRYPT_aes_context aes;
   memset(&aes, 0, sizeof(aes));
   CRYPT_AESSetKey(&aes, key, 32, true);
diff --git a/core/fpdfapi/parser/cpdf_security_handler_embeddertest.cpp b/core/fpdfapi/parser/cpdf_security_handler_embeddertest.cpp
index a9698a0..e93ca38 100644
--- a/core/fpdfapi/parser/cpdf_security_handler_embeddertest.cpp
+++ b/core/fpdfapi/parser/cpdf_security_handler_embeddertest.cpp
@@ -279,9 +279,6 @@
   VerifySavedHelloWorldDocumentWithPassword(kHotelLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kHotelUTF8);
 
-#if !defined(MEMORY_SANITIZER)
-  // TODO(crbug.com/1032090): This triggers an MSAN error.
-  // Fix and enable this code.
   ClearString();
   RemoveTrailerIdFromDocument();
   EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
@@ -292,7 +289,6 @@
   // TODO(thestig): Check and see if this regeneration is necessary.
   VerifySavedHelloWorldDocumentWithPassword(kAgeLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kAgeUTF8);
-#endif
 }
 
 TEST_F(CPDFSecurityHandlerEmbedderTest, OwnerPasswordVersion5Latin1) {
@@ -306,15 +302,11 @@
   VerifySavedHelloWorldDocumentWithPassword(kHotelLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kHotelUTF8);
 
-#if !defined(MEMORY_SANITIZER)
-  // TODO(crbug.com/1032090): This triggers an MSAN error.
-  // Fix and enable this code.
   ClearString();
   RemoveTrailerIdFromDocument();
   EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
   VerifySavedHelloWorldDocumentWithPassword(kAgeLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kAgeUTF8);
-#endif
 }
 
 TEST_F(CPDFSecurityHandlerEmbedderTest, OwnerPasswordVersion6UTF8) {
@@ -328,15 +320,11 @@
   VerifySavedHelloWorldDocumentWithPassword(kHotelLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kHotelUTF8);
 
-#if !defined(MEMORY_SANITIZER)
-  // TODO(crbug.com/1032090): This triggers an MSAN error.
-  // Fix and enable this code.
   ClearString();
   RemoveTrailerIdFromDocument();
   EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
   VerifySavedHelloWorldDocumentWithPassword(kAgeLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kAgeUTF8);
-#endif
 }
 
 TEST_F(CPDFSecurityHandlerEmbedderTest, OwnerPasswordVersion6Latin1) {
@@ -350,15 +338,11 @@
   VerifySavedHelloWorldDocumentWithPassword(kHotelLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kHotelUTF8);
 
-#if !defined(MEMORY_SANITIZER)
-  // TODO(crbug.com/1032090): This triggers an MSAN error.
-  // Fix and enable this code.
   ClearString();
   RemoveTrailerIdFromDocument();
   EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
   VerifySavedHelloWorldDocumentWithPassword(kAgeLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kAgeUTF8);
-#endif
 }
 
 TEST_F(CPDFSecurityHandlerEmbedderTest, UserPasswordVersion2UTF8) {
@@ -457,9 +441,6 @@
   VerifySavedHelloWorldDocumentWithPassword(kHotelLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kHotelUTF8);
 
-#if !defined(MEMORY_SANITIZER)
-  // TODO(crbug.com/1032090): This triggers an MSAN error.
-  // Fix and enable this code.
   ClearString();
   RemoveTrailerIdFromDocument();
   EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
@@ -469,7 +450,6 @@
   // TODO(thestig): Check and see if this regeneration is necessary.
   VerifySavedHelloWorldDocumentWithPassword(kHotelLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kHotelUTF8);
-#endif
 }
 
 TEST_F(CPDFSecurityHandlerEmbedderTest, UserPasswordVersion5Latin1) {
@@ -483,15 +463,11 @@
   VerifySavedHelloWorldDocumentWithPassword(kHotelLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kHotelUTF8);
 
-#if !defined(MEMORY_SANITIZER)
-  // TODO(crbug.com/1032090): This triggers an MSAN error.
-  // Fix and enable this code.
   ClearString();
   RemoveTrailerIdFromDocument();
   EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
   VerifySavedHelloWorldDocumentWithPassword(kHotelLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kHotelUTF8);
-#endif
 }
 
 TEST_F(CPDFSecurityHandlerEmbedderTest, UserPasswordVersion6UTF8) {
@@ -505,15 +481,11 @@
   VerifySavedHelloWorldDocumentWithPassword(kHotelLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kHotelUTF8);
 
-#if !defined(MEMORY_SANITIZER)
-  // TODO(crbug.com/1032090): This triggers an MSAN error.
-  // Fix and enable this code.
   ClearString();
   RemoveTrailerIdFromDocument();
   EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
   VerifySavedHelloWorldDocumentWithPassword(kHotelLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kHotelUTF8);
-#endif
 }
 
 TEST_F(CPDFSecurityHandlerEmbedderTest, UserPasswordVersion6Latin1) {
@@ -527,13 +499,9 @@
   VerifySavedHelloWorldDocumentWithPassword(kHotelLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kHotelUTF8);
 
-#if !defined(MEMORY_SANITIZER)
-  // TODO(crbug.com/1032090): This triggers an MSAN error.
-  // Fix and enable this code.
   ClearString();
   RemoveTrailerIdFromDocument();
   EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
   VerifySavedHelloWorldDocumentWithPassword(kHotelLatin1);
   VerifySavedHelloWorldDocumentWithPassword(kHotelUTF8);
-#endif
 }