diff --git a/Recast/Source/RecastRegion.cpp b/Recast/Source/RecastRegion.cpp
index 2bb3503..54acf4b 100644
--- a/Recast/Source/RecastRegion.cpp
+++ b/Recast/Source/RecastRegion.cpp
@@ -1575,6 +1575,13 @@ bool rcBuildRegions(rcContext* ctx, rcCompactHeightfield& chf,
 		// Make sure border will not overflow.
 		const int bw = rcMin(w, borderSize);
 		const int bh = rcMin(h, borderSize);
+
+		if (regionId > 0xFFFB)
+		{
+			ctx->log(RC_LOG_ERROR, "rcBuildRegions: Region ID overflow");
+			return false;
+		}
+		
 		// Paint regions
 		paintRectRegion(0, bw, 0, h, regionId|RC_BORDER_REG, chf, srcReg); regionId++;
 		paintRectRegion(w-bw, w, 0, h, regionId|RC_BORDER_REG, chf, srcReg); regionId++;
@@ -1622,7 +1629,15 @@ bool rcBuildRegions(rcContext* ctx, rcCompactHeightfield& chf,
 				if (i >= 0 && srcReg[i] == 0)
 				{
 					if (floodRegion(x, y, i, level, regionId, chf, srcReg, srcDist, stack))
+					{
+						if (regionId == 0xFFFF)
+						{
+							ctx->log(RC_LOG_ERROR, "rcBuildRegions: Region ID overflow");
+							return false;
+						}
+						
 						regionId++;
+					}
 				}
 			}
 		}