diff --git a/ChangeLog b/ChangeLog
index 2eb0671..40b5a00 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2021-03-23  Tatsuya Kinoshita  <tats@debian.org>
+
+	* Str.c: Reduce memory reallocation due to Strgrow.
+
+	* libwc/ucs.c:
+	Prevent unneeded memory allocation for language tags in libwc.
+	cf. https://oss-fuzz.com/testcase-detail/6275874304425984
+	Bug-Chromium: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=31397
+
 2021-03-22  Tatsuya Kinoshita  <tats@debian.org>
 
 	* libwc/ucs.c: Prevent very long language tag in libwc.