diff --git a/debian/changelog b/debian/changelog
index 8525a9e23010ee61a61e73e3c87af64aff45765a..e663d54e82e88f9076458ee659381ece96d4c2a8 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,4 +1,10 @@
-ghostscript (9.50~dfsg-ok6) yangtze; urgency=medium
+ghostscript (9.50~dfsg-ok7) yangtze; urgency=medium
+
+  * zayin CVE-2020-21890 安全更新：修复缓冲区溢出的漏洞。Ghostscript 9.50 版本存在安全漏洞，该漏洞源于 devices/gdevclj.c 的 clj_media_size 函数中存在缓冲区溢出漏洞。
+
+ -- zhangruijia <logiris@bupt.edu.cn>  Sat, 09 Dec 2023 20:04:47 +0800
+
+ ghostscript (9.50~dfsg-ok6) yangtze; urgency=medium
 
   * Update package info.
 
diff --git a/devices/gdevclj.c b/devices/gdevclj.c
index a293ec4e9e76a217272b7cd95199e6c71fb94cd6..f23baeb7058af05e3a4aee803ee688e83ee9e588 100644
--- a/devices/gdevclj.c
+++ b/devices/gdevclj.c
@@ -266,8 +266,8 @@ clj_media_size(float mediasize[2], gs_param_list *plist)
     }
 
     if (param_read_int_array(plist, "HWSize", &hwsize) == 0) {
-        mediasize[0] = ((float)hwsize.data[0]) * 72 / fres.data[0];
-        mediasize[1] = ((float)hwsize.data[1]) * 72 / fres.data[1];
+        mediasize[0] = ((float)hwsize.data[0]) * 72 / res[0];
+        mediasize[1] = ((float)hwsize.data[1]) * 72 / res[1];
         have_pagesize = 1;
     }