diff --git a/extras/vpnupgrade.sh b/extras/vpnupgrade.sh
index 3387012..e3f355e 100644
--- a/extras/vpnupgrade.sh
+++ b/extras/vpnupgrade.sh
@@ -44,7 +44,7 @@ if ! /usr/local/sbin/ipsec --version 2>/dev/null | grep -qs "Libreswan"; then
   exiterr "This script requires Libreswan already installed."
 fi
 
-if /usr/local/sbin/ipsec --version 2>/dev/null | grep -qs "$swan_ver"; then
+if /usr/local/sbin/ipsec --version 2>/dev/null | grep -qs -F "$swan_ver"; then
   echo "You already have Libreswan version $swan_ver installed! "
   echo "If you continue, the same version will be re-installed."
   echo
@@ -149,7 +149,7 @@ make -s programs && make -s install
 # Verify the install and clean up
 cd /opt/src || exiterr "Cannot enter /opt/src."
 /bin/rm -rf "/opt/src/libreswan-$swan_ver"
-if ! /usr/local/sbin/ipsec --version 2>/dev/null | grep -qs "$swan_ver"; then
+if ! /usr/local/sbin/ipsec --version 2>/dev/null | grep -qs -F "$swan_ver"; then
   exiterr "Libreswan $swan_ver failed to build."
 fi
 
diff --git a/extras/vpnupgrade_centos.sh b/extras/vpnupgrade_centos.sh
index 4590dc3..f5d79bc 100644
--- a/extras/vpnupgrade_centos.sh
+++ b/extras/vpnupgrade_centos.sh
@@ -40,7 +40,7 @@ if ! /usr/local/sbin/ipsec --version 2>/dev/null | grep -qs "Libreswan"; then
   exiterr "This script requires Libreswan already installed."
 fi
 
-if /usr/local/sbin/ipsec --version 2>/dev/null | grep -qs "$swan_ver"; then
+if /usr/local/sbin/ipsec --version 2>/dev/null | grep -qs -F "$swan_ver"; then
   echo "You already have Libreswan version $swan_ver installed! "
   echo "If you continue, the same version will be re-installed."
   echo
@@ -141,7 +141,7 @@ make -s programs && make -s install
 # Verify the install and clean up
 cd /opt/src || exiterr "Cannot enter /opt/src."
 /bin/rm -rf "/opt/src/libreswan-$swan_ver"
-if ! /usr/local/sbin/ipsec --version 2>/dev/null | grep -qs "$swan_ver"; then
+if ! /usr/local/sbin/ipsec --version 2>/dev/null | grep -qs -F "$swan_ver"; then
   exiterr "Libreswan $swan_ver failed to build."
 fi
 
diff --git a/vpnsetup.sh b/vpnsetup.sh
index 2f3c111..8d46ad5 100755
--- a/vpnsetup.sh
+++ b/vpnsetup.sh
@@ -189,7 +189,7 @@ make -s programs && make -s install
 # Verify the install and clean up
 cd /opt/src || exiterr "Cannot enter /opt/src."
 /bin/rm -rf "/opt/src/libreswan-$swan_ver"
-if ! /usr/local/sbin/ipsec --version 2>/dev/null | grep -qs "$swan_ver"; then
+if ! /usr/local/sbin/ipsec --version 2>/dev/null | grep -qs -F "$swan_ver"; then
   exiterr "Libreswan $swan_ver failed to build."
 fi
 
diff --git a/vpnsetup_centos.sh b/vpnsetup_centos.sh
index 80b83aa..f00c453 100755
--- a/vpnsetup_centos.sh
+++ b/vpnsetup_centos.sh
@@ -176,7 +176,7 @@ make -s programs && make -s install
 # Verify the install and clean up
 cd /opt/src || exiterr "Cannot enter /opt/src."
 /bin/rm -rf "/opt/src/libreswan-$swan_ver"
-if ! /usr/local/sbin/ipsec --version 2>/dev/null | grep -qs "$swan_ver"; then
+if ! /usr/local/sbin/ipsec --version 2>/dev/null | grep -qs -F "$swan_ver"; then
   exiterr "Libreswan $swan_ver failed to build."
 fi