diff --git a/chapter06/ed-exp.xml b/chapter06/ed-exp.xml
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-<sect2>
-<title>Command explanations</title>
-
-<para><userinput>patch -Np1 -i ../ed-&ed-version;.patch:</userinput> This
-patch fixes a symlink vulnerability in ed. The ed executable creates files
-in /tmp with predictable names. By using various symlink attacks, it is
-possible to have ed write to files it should not, change the permissions
-of files, etc.</para>
-
-</sect2>
-