diff --git a/app/templates/packages/release_new.html b/app/templates/packages/release_new.html
index 4dd2db2..f2f23a5 100644
--- a/app/templates/packages/release_new.html
+++ b/app/templates/packages/release_new.html
@@ -37,7 +37,8 @@
 		{{ render_radio_field(form.uploadOpt) }}
 
 		{% if package.repo %}
-			{{ render_field(form.vcsLabel, placeholder="Leave blank to use default branch", class_="mt-3") }}
+			{{ render_field(form.vcsLabel, placeholder="Leave blank to use default branch", class_="mt-3",
+					pattern="[A-Za-z0-9/._-]+") }}
 		{% endif %}
 
 		{{ render_field(form.fileUpload, fieldclass="form-control-file", class_="mt-3", accept=".zip") }}