Index: subversion/libsvn_repos/repos.c
===================================================================
--- subversion/libsvn_repos/repos.c	(revision 1603773)
+++ subversion/libsvn_repos/repos.c	(working copy)
@@ -280,6 +280,13 @@
   "# http://svn.apache.org/repos/asf/subversion/trunk/tools/hook-scripts/ and"        NL \
   "# http://svn.apache.org/repos/asf/subversion/trunk/contrib/hook-scripts/"          NL
 
+#define HOOKS_QUOTE_ARGUMENTS_TEXT                                            \
+  "# CAUTION:"                                                             NL \
+  "# For security reasions, you MUST always properly qoute arguments when" NL \
+  "# you use them. For example, a malicious client could try to set a"     NL \
+  "# revision property named \"foo; rm -rf /;\"."                          NL \
+  "# For similar reasons, you should also add a trailing @ to URLs which"  NL \
+  "# are passed to SVN commands which accept URLs with peg revisions."     NL
 
 static svn_error_t *
 create_hooks(svn_repos_t *repos, apr_pool_t *pool)
@@ -354,6 +361,8 @@
 "# "                                                                         NL
 HOOKS_ENVIRONMENT_TEXT
 "# "                                                                         NL
+HOOKS_QUOTE_ARGUMENTS_TEXT
+"# "                                                                         NL
 "# Here is an example hook script, for a Unix /bin/sh interpreter."          NL
 PREWRITTEN_HOOKS_TEXT
 ""                                                                           NL
@@ -439,6 +448,8 @@
 "#"                                                                          NL
 HOOKS_ENVIRONMENT_TEXT
 "# "                                                                         NL
+HOOKS_QUOTE_ARGUMENTS_TEXT
+"# "                                                                         NL
 "# Here is an example hook script, for a Unix /bin/sh interpreter."          NL
 PREWRITTEN_HOOKS_TEXT
 ""                                                                           NL
@@ -522,6 +533,8 @@
 "#"                                                                          NL
 HOOKS_ENVIRONMENT_TEXT
 "# "                                                                         NL
+HOOKS_QUOTE_ARGUMENTS_TEXT
+"# "                                                                         NL
 "# Here is an example hook script, for a Unix /bin/sh interpreter."          NL
 PREWRITTEN_HOOKS_TEXT
 ""                                                                           NL
@@ -594,6 +607,8 @@
 "# '"SCRIPT_NAME".bat' or '"SCRIPT_NAME".exe',"                              NL
 "# but the basic idea is the same."                                          NL
 "#"                                                                          NL
+HOOKS_QUOTE_ARGUMENTS_TEXT
+"# "                                                                         NL
 "# Here is an example hook script, for a Unix /bin/sh interpreter:"          NL
 ""                                                                           NL
 "REPOS=\"$1\""                                                               NL
@@ -681,6 +696,8 @@
 "# '"SCRIPT_NAME".bat' or '"SCRIPT_NAME".exe',"                              NL
 "# but the basic idea is the same."                                          NL
 "#"                                                                          NL
+HOOKS_QUOTE_ARGUMENTS_TEXT
+"# "                                                                         NL
 "# Here is an example hook script, for a Unix /bin/sh interpreter:"          NL
 ""                                                                           NL
 "REPOS=\"$1\""                                                               NL
@@ -767,6 +784,8 @@
 "# "                                                                         NL
 HOOKS_ENVIRONMENT_TEXT
 "# "                                                                         NL
+HOOKS_QUOTE_ARGUMENTS_TEXT
+"# "                                                                         NL
 "# Here is an example hook script, for a Unix /bin/sh interpreter."          NL
 PREWRITTEN_HOOKS_TEXT
 ""                                                                           NL
@@ -830,6 +849,8 @@
 "# '"SCRIPT_NAME".bat' or '"SCRIPT_NAME".exe',"                              NL
 "# but the basic idea is the same."                                          NL
 "# "                                                                         NL
+HOOKS_QUOTE_ARGUMENTS_TEXT
+"# "                                                                         NL
 "# Here is an example hook script, for a Unix /bin/sh interpreter:"          NL
 ""                                                                           NL
 "REPOS=\"$1\""                                                               NL
@@ -888,6 +909,8 @@
 "# '"SCRIPT_NAME".bat' or '"SCRIPT_NAME".exe',"                              NL
 "# but the basic idea is the same."                                          NL
 "# "                                                                         NL
+HOOKS_QUOTE_ARGUMENTS_TEXT
+"# "                                                                         NL
 "# Here is an example hook script, for a Unix /bin/sh interpreter:"          NL
 ""                                                                           NL
 "REPOS=\"$1\""                                                               NL
@@ -951,6 +974,8 @@
 "# "                                                                         NL
 HOOKS_ENVIRONMENT_TEXT
 "# "                                                                         NL
+HOOKS_QUOTE_ARGUMENTS_TEXT
+"# "                                                                         NL
 "# Here is an example hook script, for a Unix /bin/sh interpreter."          NL
 PREWRITTEN_HOOKS_TEXT
 ""                                                                           NL