fix link

[web.git] / ralf / _posts / 2018-06-02-mailman-subscription-spam.md

diff --git a/ralf/_posts/2018-06-02-mailman-subscription-spam.md b/ralf/_posts/2018-06-02-mailman-subscription-spam.md
index 237153c026524132fbb389c5e69bb9578b207158..e8d557c48e6b23b4a98a54d4719204988ae7ac0b 100644 (file)
--- a/ralf/_posts/2018-06-02-mailman-subscription-spam.md
+++ b/ralf/_posts/2018-06-02-mailman-subscription-spam.md
@@ -20,14 +20,17 @@ spam.  So, more than enough reasons to try and stop this.
 ### The Big Guns
 
 My first reaction was to go and look for a way to add a CAPTCHA to the
-subscription page.  Unfortunately, Mailman itself does not support a CAPTCHA (at
-least not Mailman 2), and the existing patches I found were all about adding
-support for Google's reCAPTCHA.  I am not going to expose my users to Google's
-tracking like that, nor am I willing to actively discriminate against people not
-having Google accounts (reCAPTCHA is much more annoying if Google can't track
-you because you are not logged in), so reCAPTCHA was clearly not an option.
-Instead, the plan was to look at one of these patches and implement a simple
-question-and-answer CAPTCHA myself.
+subscription page.  Unfortunately, Mailman 2 itself only very recently (with
+version 2.1.26) gained support for CAPTCHAs, and even that just supports
+Google's reCAPTCHA.  I am not going to expose my users to Google's tracking like
+that, nor am I willing to actively discriminate against people not having Google
+accounts (reCAPTCHA is much more annoying if Google can't track you because you
+are not logged in), so reCAPTCHA was clearly not an option.  Instead, the plan
+was to look at one of the patches that add CAPTCHA support to older versions of
+Mailman and implement a simple question-and-answer CAPTCHA myself.
+
+**Update:** I previously claimed Mailman 2 does not support CAPTCHAs at all,
+  which turned out to be incorrect. **/Update**
 
 ### Keep It Simple
 
@@ -42,9 +45,10 @@ have found my servers so far are much less patient than that, just setting
 spam.
 
 So, if you are reading this and running a Mailman installation: **Please set
-`SUBSCRIBE_FORM_SECRET` and protect your setup against abuse!**  Just run `pwgen
-16` to get some random string, and then add `SUBSCRIBE_FORM_SECRET = "<random
-string here>"` to `/etc/mailman/mm_cfg.py`.  It's really that simple!  Just a
+`SUBSCRIBE_FORM_SECRET` and protect your setup against abuse!** Just run
+`openssl rand -base64 18` to get some random string, and then add
+`SUBSCRIBE_FORM_SECRET = "<random string here>"` to `/etc/mailman/mm_cfg.py`.
+It's really that simple!  Just a
 [four-line patch in my Ansible playbook](https://git.ralfj.de/ansible.git/commitdiff/937b170594be82e500ae726dc47de8ca9ef3dfcf)
 to get this rolled out to all servers.  Note that you need to be at least on
 Mailman 2.1.16 for this to work; all currently supported versions of Debian come
@@ -53,7 +57,5 @@ with a recent enough version (if you use backports on Debian 7 "Wheezy").
 The more people do this, the more it will help to stop this kind of spam.  Or
 rather, it'll force the spammers to upgrade their game.  I assume eventually I
 *will* have to add a CAPTCHA.  Or maybe there is a simple and reliable way to
-migrate to Mailman 3 before that happens---and maybe that will have a CAPTCHA.
-(Though, from a quick search, it doesn't seem like it does, which I find pretty
-surprising.  If my tiny servers are abused like this, I assume it's a really
-common problem and Mailman should protect against it per default.)
+migrate to Mailman 3 before that happens---and maybe that will have more
+reasonable CAPTCHA options, something beyond just reCAPTCHA.