diff --git a/libwvdrmengine/oemcrypto/ref/src/oemcrypto_engine_ref.h b/libwvdrmengine/oemcrypto/ref/src/oemcrypto_engine_ref.h
index dd5a5311..ecf816a9 100644
--- a/libwvdrmengine/oemcrypto/ref/src/oemcrypto_engine_ref.h
+++ b/libwvdrmengine/oemcrypto/ref/src/oemcrypto_engine_ref.h
@@ -152,6 +152,10 @@ class CryptoEngine {
   // Rate limit for nonce generation.  Default to 20 nonce/second.
   virtual int nonce_flood_count() { return 20; }
 
+  // Limit for size of usage table.  If this is zero, then the
+  // size is unlimited -- or limited only by memory size.
+  virtual size_t max_usage_table_size() { return 0; }
+
   // Set destination pointer based on the output destination description.
   OEMCryptoResult SetDestination(OEMCrypto_DestBufferDesc* out_description,
                                  size_t data_length, uint8_t subsample_flags);
diff --git a/libwvdrmengine/oemcrypto/ref/src/oemcrypto_usage_table_ref.cpp b/libwvdrmengine/oemcrypto/ref/src/oemcrypto_usage_table_ref.cpp
index 5373d5da..b91ed78b 100644
--- a/libwvdrmengine/oemcrypto/ref/src/oemcrypto_usage_table_ref.cpp
+++ b/libwvdrmengine/oemcrypto/ref/src/oemcrypto_usage_table_ref.cpp
@@ -380,6 +380,11 @@ OEMCryptoResult UsageTable::CreateNewUsageEntry(SessionContext* session,
   if (!entry) return OEMCrypto_ERROR_UNKNOWN_FAILURE;
   if (!usage_entry_number) return OEMCrypto_ERROR_UNKNOWN_FAILURE;
   uint32_t index = generation_numbers_.size();
+  size_t max = ce_->max_usage_table_size();
+  if (max > 0 && index >= max) {
+    LOGE("Too many usage entries: %d/%d", index, max);
+    return OEMCrypto_ERROR_INSUFFICIENT_RESOURCES;
+  }
   UsageTableEntry* new_entry = MakeEntry(index);
   generation_numbers_.push_back(master_generation_number_);
   sessions_.push_back(session);
@@ -404,6 +409,11 @@ OEMCryptoResult UsageTable::LoadUsageEntry(SessionContext* session,
     LOGE("LoadUsageEntry: index %d used by other session.", index);
     return OEMCrypto_ERROR_INVALID_SESSION;
   }
+  size_t max = ce_->max_usage_table_size();
+  if (max > 0 && index >= max) {
+    LOGE("Too many usage entries: %d/%d", index, max);
+    return OEMCrypto_ERROR_INSUFFICIENT_RESOURCES;
+  }
   UsageTableEntry* new_entry = MakeEntry(index);
 
   OEMCryptoResult status = new_entry->LoadData(ce_, index, buffer);
@@ -512,6 +522,12 @@ OEMCryptoResult UsageTable::LoadUsageTableHeader(
   if (!LoadGenerationNumber(false)) return OEMCrypto_ERROR_UNKNOWN_FAILURE;
 
   if (buffer.size() < SignedHeaderSize(0)) return OEMCrypto_ERROR_SHORT_BUFFER;
+  size_t max = ce_->max_usage_table_size();
+  if (max > 0 && buffer.size() > SignedHeaderSize(max)) {
+    LOGE("Header too big: %zd bytes/%zd bytes",
+         buffer.size(), SignedHeaderSize(max));
+    return OEMCrypto_ERROR_INSUFFICIENT_RESOURCES;
+  }
   std::vector<uint8_t> clear_buffer(buffer.size());
   SignedHeaderBlock* clear =
       reinterpret_cast<SignedHeaderBlock*>(&clear_buffer[0]);