diff --git a/src/libraries/System.Private.CoreLib/src/CodeAnalysis.ruleset b/src/libraries/System.Private.CoreLib/src/CodeAnalysis.ruleset
index 975613f0641d3134b21ae873df83dd09a58b275e..14b8f2b509a815debf109afddd1273e7adce3299 100644
--- a/src/libraries/System.Private.CoreLib/src/CodeAnalysis.ruleset
+++ b/src/libraries/System.Private.CoreLib/src/CodeAnalysis.ruleset
@@ -71,6 +71,7 @@
     <Rule Id="CA5369" Action="None" /> <!-- Use XmlReader For Deserialize -->
     <Rule Id="CA5371" Action="None" /> <!-- Use XmlReader For Schema Read -->
     <Rule Id="CA5372" Action="None" /> <!-- Use XmlReader For XPathDocument -->
+    <Rule Id="CA5397" Action="None" /> <!-- Security protocol version is deprecated -->
   </Rules>
   <Rules AnalyzerId="StyleCop.Analyzers" RuleNamespace="StyleCop.Analyzers">
     <Rule Id="AD0001" Action="None" /> <!-- Analyzer threw an exception -->