diff --git a/fix-undefined-buffer-detected-by-oss-fuzz.patch b/fix-undefined-buffer-detected-by-oss-fuzz.patch
new file mode 100644
index 0000000..5a94ce0
--- /dev/null
+++ b/fix-undefined-buffer-detected-by-oss-fuzz.patch
@@ -0,0 +1,30 @@
+From fbc28a919107bb6fbdceb2d3dfe610ddcbc5ac89 Mon Sep 17 00:00:00 2001
+From: fangyufa <fangyufa1@huawei.com>
+Date: Tue, 3 Dec 2019 15:42:06 +0800
+Subject: [PATCH] zlib: fix undefined buffer detected by oss-fuzz
+
+this patch fixes a use of uninitialized value discovered by one of the
+fuzzers of the oss-fuzz project:
+https://github.com/google/oss-fuzz/blob/master/projects/zlib/example_dict_fuzzer.c
+clear out s->prev buffer to avoid undefined behavior
+
+signed-off-by: fangyufa <fangyufa1@huawei.com>
+---
+ zlib-1.2.11/deflate.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/deflate.c b/deflate.c
+index 4c42259..a03bef2 100644
+--- a/deflate.c
++++ b/deflate.c
+@@ -329,6 +329,7 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
+ 
+     s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte));
+     s->prev   = (Posf *)  ZALLOC(strm, s->w_size, sizeof(Pos));
++    memset(s->prev, 0, s->w_size*sizeof(Pos));
+     s->head   = (Posf *)  ZALLOC(strm, s->hash_size, sizeof(Pos));
+ 
+     s->high_water = 0;      /* nothing written to s->window yet */
+-- 
+2.19.1
+
diff --git a/zlib.spec b/zlib.spec
index e0626d0..881c51c 100644
--- a/zlib.spec
+++ b/zlib.spec
@@ -1,6 +1,6 @@
 Name:             zlib
 Version:          1.2.11
-Release:          16
+Release:          17
 Summary:          A lossless data-compression library
 License:          zlib and Boost
 URL:              http://www.zlib.net
@@ -16,6 +16,8 @@ Patch3:           0003-arm64-specific-build-patch.patch
 Patch4:           0004-zlib-Optimize-CRC32.patch
 %endif
 
+Patch6000:        fix-undefined-buffer-detected-by-oss-fuzz.patch
+
 BuildRequires:    automake, autoconf, libtool
 
 %description
@@ -115,7 +117,11 @@ make test
 %{_libdir}/pkgconfig/minizip.pc
 
 %changelog
+* Sat Dec 21 2019 openEuler Buildteam <buildteam@openeuler.org> - 1.2.11-17
+- Fix undefined buffer detected by oss-fuzz
+
 * Tue Dec 3 2019 liqiang <liqiang64@huawei.com> - 1.2.11-16
 - Optimize CRC32 by NEON
+
 * Thu Sep 5 2019 dongjian <dongjian13@huawei.com> - 1.2.11-15
 - Rebuild the zlib and fix description