Update ChangeLog

ChangeLog

@@ -33,7 +33,10 @@ releases.
 * filter.d/dovecot.conf:
     - fixed failregex, see gh-1879 (partially cherry-picked from gh-1880)
     - extended to match pam_authenticate failures with "Permission denied" (gh-1897)
-* filter.d/exim.conf - fixed failregex for case of flood attempts with `D=0s` (gh-1887)
+* filter.d/exim.conf
+    - fixed failregex for case of flood attempts with `D=0s` (gh-1887)
+    - fixed failregex of "AUTH command used when not advertised" to better handle the foreign
+      input SMTP command (lower/mixed case auth command, prevent injection) (gh-1979)
 * filter.d/postfix-*.conf - added optional port regex (gh-1902)
 
 ### New Features