diff --git a/Changes b/Changes
index 5053279e0b..ae32797428 100644
--- a/Changes
+++ b/Changes
@@ -1,6 +1,14 @@
-10.5.x.x (relative to 10.5.18.1)
+10.5.x.x (relative to 10.5.18.2)
 ========
 
+10.5.18.2 (relative to 10.5.18.1)
+========
+
+Fixes
+-----
+
+- VDB : Mitigated lack of thread safety in `hash()`
+
 10.5.18.1 (relative to 10.5.18.0)
 ========
 
diff --git a/SConstruct b/SConstruct
index 2009706062..bcac6be15a 100644
--- a/SConstruct
+++ b/SConstruct
@@ -55,7 +55,7 @@ SConsignFile()
 ieCoreMilestoneVersion = 10 # for announcing major milestones - may contain all of the below
 ieCoreMajorVersion = 5 # backwards-incompatible changes
 ieCoreMinorVersion = 18 # new backwards-compatible features
-ieCorePatchVersion = 1 # bug fixes
+ieCorePatchVersion = 2 # bug fixes
 ieCoreVersionSuffix = "" # used for alpha/beta releases. Example: "a1", "b2", etc.
 
 ###########################################################################################
diff --git a/src/IECoreVDB/VDBObject.cpp b/src/IECoreVDB/VDBObject.cpp
index 41b09d6328..d4449bf805 100644
--- a/src/IECoreVDB/VDBObject.cpp
+++ b/src/IECoreVDB/VDBObject.cpp
@@ -424,11 +424,12 @@ openvdb::GridBase::Ptr VDBObject::HashedGrid::grid() const
 
 IECore::MurmurHash VDBObject::HashedGrid::hash() const
 {
+	/// \todo This is not threadsafe. Fix it.
 	if( !m_hashValid )
 	{
-		m_hash = IECore::MurmurHash();
+		IECore::MurmurHash h;
 
-		MurmurHashSink sink( m_hash );
+		MurmurHashSink sink( h );
 		boost::iostreams::stream<MurmurHashSink> hashStream( sink );
 
 		openvdb::io::StreamMetadata::Ptr streamMetadata ( new openvdb::io::StreamMetadata() );
@@ -439,6 +440,7 @@ IECore::MurmurHash VDBObject::HashedGrid::hash() const
 		m_grid->writeBuffers( hashStream );
 		m_grid->writeTransform( hashStream );
 
+		m_hash = h;
 		m_hashValid = true;
 	}