diff --git a/jjb/shell/tagcollisionreject.sh b/jjb/shell/tagcollisionreject.sh
index a7ba04e..4a791b6 100755
--- a/jjb/shell/tagcollisionreject.sh
+++ b/jjb/shell/tagcollisionreject.sh
@@ -107,7 +107,7 @@
     for df_parent in "${df_parents[@]}"
     do
 
-      df_pattern="FROM (.*):(.*)"
+      df_pattern="FROM ([^:]*):(.*)"
       if [[ "$df_parent" =~ $df_pattern ]]
       then
 
@@ -117,6 +117,10 @@
         if [[ "${p_version}" =~ ^([0-9]+)\.([0-9]+)\.([0-9]+)$ ]]
         then
           echo "  OK: Parent '$p_image:$p_version' is a released SemVer version"
+        elif [[ "${p_version}" =~ ^.*@sha256:[0-9a-f]{64}.*$ ]]
+        then
+          # allow sha256 hashes to be used as version specifiers
+          echo "  OK: Parent '$p_image:$p_version' is using a specific sha256 hash as a version"
         elif [[ "${p_version}" =~ ^.*([0-9]+)\.([0-9]+).*$ ]]
         then
           # handle non-SemVer versions that have a Major.Minor version specifier in the name
diff --git a/jjb/shell/versiontag.sh b/jjb/shell/versiontag.sh
index 41971ce..d4091e6 100755
--- a/jjb/shell/versiontag.sh
+++ b/jjb/shell/versiontag.sh
@@ -108,7 +108,7 @@
     for df_parent in "${df_parents[@]}"
     do
 
-      df_pattern="FROM (.*):(.*)"
+      df_pattern="FROM ([^:]*):(.*)"
       if [[ "$df_parent" =~ $df_pattern ]]
       then
 
@@ -118,6 +118,10 @@
         if [[ "${p_version}" =~ ^([0-9]+)\.([0-9]+)\.([0-9]+)$ ]]
         then
           echo "  OK: Parent '$p_image:$p_version' is a released SemVer version"
+        elif [[ "${p_version}" =~ ^.*@sha256:[0-9a-f]{64}.*$ ]]
+        then
+          # allow sha256 hashes to be used as version specifiers
+          echo "  OK: Parent '$p_image:$p_version' is using a specific sha256 hash as a version"
         elif [[ "${p_version}" =~ ^.*([0-9]+)\.([0-9]+).*$ ]]
         then
           # handle non-SemVer versions that have a Major.Minor version specifier in the name