There was a buffer overflow detected in list.c file where cfactorstr[] had an insufficient size (10). It was fixed in unzip beta versions and expanded to size 12 but I think it's still insufficient. The right size should be 13 (sgn (1), int (10), % (1), nul (1)).

Also, replacing sprintf() by snprintf() might make the code more robust.
Kudos to Josef Möllers (josef.moellers@suse.com).

Refs: https://sourceforge.net/p/infozip/bugs/53/
      CVE-2018-18384

diff --git a/list.c b/list.c
index 15e0011..a770ae7 100644
--- a/list.c
+++ b/list.c
@@ -97,7 +97,7 @@ int list_files(__G)    /* return PK-type error code */
 {
     int do_this_file=FALSE, cfactor, error, error_in_archive=PK_COOL;
 #ifndef WINDLL
-    char sgn, cfactorstr[10];
+    char sgn, cfactorstr[1+10+1+1];	/* <sgn><int>%NUL */
     int longhdr=(uO.vflag>1);
 #endif
     int date_format;
@@ -378,9 +378,9 @@ int list_files(__G)    /* return PK-type error code */
             }
 #else /* !WINDLL */
             if (cfactor == 100)
-                sprintf(cfactorstr, LoadFarString(CompFactor100));
+                snprintf(cfactorstr, sizeof(cfactorstr), LoadFarString(CompFactor100));
             else
-                sprintf(cfactorstr, LoadFarString(CompFactorStr), sgn, cfactor);
+                snprintf(cfactorstr, sizeof(cfactorstr), LoadFarString(CompFactorStr), sgn, cfactor);
             if (longhdr)
                 Info(slide, 0, ((char *)slide, LoadFarString(LongHdrStats),
                   FmZofft(G.crec.ucsize, "8", "u"), methbuf,
@@ -460,9 +460,9 @@ int list_files(__G)    /* return PK-type error code */
 
 #else /* !WINDLL */
         if (cfactor == 100)
-            sprintf(cfactorstr, LoadFarString(CompFactor100));
+            snprintf(cfactorstr, sizeof(cfactorstr), LoadFarString(CompFactor100));
         else
-            sprintf(cfactorstr, LoadFarString(CompFactorStr), sgn, cfactor);
+            snprintf(cfactorstr, sizeof(cfactorstr), LoadFarString(CompFactorStr), sgn, cfactor);
         if (longhdr) {
             Info(slide, 0, ((char *)slide, LoadFarString(LongFileTrailer),
               FmZofft(tot_ucsize, "8", "u"), FmZofft(tot_csize, "8", "u"),