diff --git a/libavcodec/exr.c b/libavcodec/exr.c
index 444af17778..5253cc3f13 100644
--- a/libavcodec/exr.c
+++ b/libavcodec/exr.c
@@ -899,7 +899,7 @@ static int pxr24_uncompress(EXRContext *s, const uint8_t *src,
 
 static void unpack_14(const uint8_t b[14], uint16_t s[16])
 {
-    unsigned short shift = (b[ 2] >> 2);
+    unsigned short shift = (b[ 2] >> 2) & 15;
     unsigned short bias = (0x20 << shift);
     int i;