Updated Release notes

Issue-ID: VNFSDK-830

Signed-off-by: sharath reddy <bs.reddy@huawei.com>
Change-Id: I3c39b68c3be619a8b7c7182f2556dc47a25df120
diff --git a/docs/release-notes.rst b/docs/release-notes.rst
index 7e6bb5b..4205bf4 100644
--- a/docs/release-notes.rst
+++ b/docs/release-notes.rst
@@ -14,6 +14,14 @@
    * developing tools for vendor CI/CD toolchains
    * developing validation and testing tools
 
+Istanbul Maintenance release
+---------------------------------
+
+As following VNFSDK components are having log4j transitive dependencies, they are verified for log4j vulnerability and no issues identified:
+
+ * refrepo
+ * validation
+
 Version: 1.6.3
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