diff --git a/poppler/GfxState.cc b/poppler/GfxState.cc
index e3413e5..2965e37 100644
--- a/poppler/GfxState.cc
+++ b/poppler/GfxState.cc
@@ -2161,10 +2161,16 @@ GfxColorSpace *GfxSeparationColorSpace::parse(Array *arr, Gfx *gfx, int recursio
   if (!(funcA = Function::parse(&obj1))) {
     goto err4;
   }
+  if (funcA->getInputSize() != 1) {
+    error(errSyntaxWarning, -1, "Bad SeparationColorSpace function");
+    goto err5;
+  }
   obj1.free();
   cs = new GfxSeparationColorSpace(nameA, altA, funcA);
   return cs;
 
+ err5:
+  delete funcA;
  err4:
   delete altA;
  err3:
@@ -3084,6 +3090,10 @@ void GfxUnivariateShading::getColor(double t, GfxColor *color) {
       out[i] = 0;
     }
     for (i = 0; i < nFuncs; ++i) {
+      if (funcs[i]->getInputSize() != 1) {
+        error(errSyntaxWarning, -1, "Invalid shading function (input != 1)");
+        break;
+      }
       funcs[i]->transform(&t, &out[i]);
     }
   }