diff --git a/sign-security.sh b/sign-security.sh
new file mode 100755
index 0000000..7715158
--- /dev/null
+++ b/sign-security.sh
@@ -0,0 +1,10 @@
+# This script must be run in the directory of the repo
+if [[ -f "security.txt" ]]; then
+    TODAY=$(date +%Y-%m-%d)
+    EXPIRE=$(date +%Y-%m-%dT00:00:00.000Z -d "$TODAY + 6 month")
+    cp security.txt temp-security.txt
+    echo "Expires: $EXPIRE" >> temp-security.txt
+    gpg --clearsign --default-key psirt@linaro.org --passphrase Radial-swipe-Division-Fault-2Accustom-Jaw6-4duration-potato temp-security.txt
+    rm temp-security.txt
+    mv temp-security.txt.asc security.txt.asc
+fi