diff --git a/core/dovecot/Dockerfile b/core/dovecot/Dockerfile
index f6f8f2e2..e1c20eff 100644
--- a/core/dovecot/Dockerfile
+++ b/core/dovecot/Dockerfile
@@ -1,4 +1,4 @@
-ARG DISTRO=alpine:3.12
+ARG DISTRO=alpine:3.13
 FROM $DISTRO as builder
 WORKDIR /tmp
 RUN apk add git build-base automake autoconf libtool dovecot-dev xapian-core-dev icu-dev
diff --git a/towncrier/newsfragments/1720.bugfix b/towncrier/newsfragments/1720.bugfix
new file mode 100644
index 00000000..0bf2b8e6
--- /dev/null
+++ b/towncrier/newsfragments/1720.bugfix
@@ -0,0 +1,2 @@
+Fix CVE-2020-25275 and CVE-2020-24386 by using alpine 3.13 for
+dovecot which contains a fixed dovecot version.