diff --git a/cmd/aws-iam-authenticator/root.go b/cmd/aws-iam-authenticator/root.go
index ac741936f..435ad1630 100644
--- a/cmd/aws-iam-authenticator/root.go
+++ b/cmd/aws-iam-authenticator/root.go
@@ -102,6 +102,7 @@ func getConfig() (config.Config, error) {
 		EC2DescribeInstancesQps:           viper.GetInt("server.ec2DescribeInstancesQps"),
 		EC2DescribeInstancesBurst:         viper.GetInt("server.ec2DescribeInstancesBurst"),
 		ScrubbedAWSAccounts:               viper.GetStringSlice("server.scrubbedAccounts"),
+		EKSYaml:                           viper.GetBool("server.eksyaml"),
 	}
 	if err := viper.UnmarshalKey("server.mapRoles", &cfg.RoleMappings); err != nil {
 		return cfg, fmt.Errorf("invalid server role mappings: %v", err)
diff --git a/pkg/config/types.go b/pkg/config/types.go
index 5d056aafe..16da2cc36 100644
--- a/pkg/config/types.go
+++ b/pkg/config/types.go
@@ -32,8 +32,8 @@ type IdentityMapping struct {
 // list of Kubernetes groups. The username and groups are specified as templates
 // that may optionally contain two template parameters:
 //
-//  1) "{{AccountID}}" is the 12 digit AWS ID.
-//  2) "{{SessionName}}" is the role session name.
+//  1. "{{AccountID}}" is the 12 digit AWS ID.
+//  2. "{{SessionName}}" is the role session name.
 //
 // The meaning of SessionName depends on the type of entity assuming the role.
 // In the case of an EC2 instance role this will be the EC2 instance ID. In the
@@ -169,4 +169,5 @@ type Config struct {
 	// understand we don't need to change
 	EC2DescribeInstancesQps   int
 	EC2DescribeInstancesBurst int
+	EKSYaml                   bool
 }
diff --git a/pkg/mapper/configmap/configmap.go b/pkg/mapper/configmap/configmap.go
index 350cab0c6..6edbea783 100644
--- a/pkg/mapper/configmap/configmap.go
+++ b/pkg/mapper/configmap/configmap.go
@@ -115,15 +115,19 @@ func ParseMap(m map[string]string) (userMappings []config.UserMapping, roleMappi
 	rawUserMappings := make([]config.UserMapping, 0)
 	userMappings = make([]config.UserMapping, 0)
 	if userData, ok := m["mapUsers"]; ok {
-		userJson, err := utilyaml.ToJSON([]byte(userData))
+		if EKSYaml {
+			//use Lenient Yaml Parser
+			err = yaml.Unmarshal([]byte(userData), &rawUserMappings)
+		} else {
+			//use Strict Yaml Parser
+			userJson, err := utilyaml.ToJSON([]byte(userData))
+			if err == nil {
+				err = json.Unmarshal(userJson, &rawUserMappings)
+			}
+		}
 		if err != nil {
 			errs = append(errs, err)
 		} else {
-			err = json.Unmarshal(userJson, &rawUserMappings)
-			if err != nil {
-				errs = append(errs, err)
-			}
-
 			for _, userMapping := range rawUserMappings {
 				err = userMapping.Validate()
 				if err != nil {
@@ -138,15 +142,20 @@ func ParseMap(m map[string]string) (userMappings []config.UserMapping, roleMappi
 	rawRoleMappings := make([]config.RoleMapping, 0)
 	roleMappings = make([]config.RoleMapping, 0)
 	if roleData, ok := m["mapRoles"]; ok {
-		roleJson, err := utilyaml.ToJSON([]byte(roleData))
-		if err != nil {
-			errs = append(errs, err)
+		if EKSYaml {
+			//use Lenient Yaml Parser
+			err = yaml.Unmarshal([]byte(roleData), &rawRoleMappings)
 		} else {
-			err = json.Unmarshal(roleJson, &rawRoleMappings)
-			if err != nil {
-				errs = append(errs, err)
+			//use Strict Yaml Parser
+			roleJson, err := utilyaml.ToJSON([]byte(roleData))
+			if err == nil {
+				err = json.Unmarshal(roleJson, &rawRoleMappings)
 			}
+		}
 
+		if err != nil {
+			errs = append(errs, err)
+		} else {
 			for _, roleMapping := range rawRoleMappings {
 				err = roleMapping.Validate()
 				if err != nil {
diff --git a/pkg/mapper/configmap/configmap_test.go b/pkg/mapper/configmap/configmap_test.go
index ff6bb64fd..d0103ae41 100644
--- a/pkg/mapper/configmap/configmap_test.go
+++ b/pkg/mapper/configmap/configmap_test.go
@@ -17,6 +17,7 @@ import (
 
 func init() {
 	config.SSORoleMatchEnabled = true
+	EKSYaml = true
 }
 
 var (
diff --git a/pkg/mapper/configmap/mapper.go b/pkg/mapper/configmap/mapper.go
index 6088bd34c..ff0c33c4d 100644
--- a/pkg/mapper/configmap/mapper.go
+++ b/pkg/mapper/configmap/mapper.go
@@ -13,7 +13,10 @@ type ConfigMapMapper struct {
 
 var _ mapper.Mapper = &ConfigMapMapper{}
 
+var EKSYaml = false
+
 func NewConfigMapMapper(cfg config.Config) (*ConfigMapMapper, error) {
+	EKSYaml = cfg.EKSYaml
 	ms, err := New(cfg.Master, cfg.Kubeconfig)
 	if err != nil {
 		return nil, err
diff --git a/pkg/mapper/configmap/yaml_test.go b/pkg/mapper/configmap/yaml_test.go
index 81222b4fc..1a9e15ca5 100644
--- a/pkg/mapper/configmap/yaml_test.go
+++ b/pkg/mapper/configmap/yaml_test.go
@@ -21,6 +21,11 @@ import (
 
 var log = logrus.New()
 
+func init() {
+	config.SSORoleMatchEnabled = true
+	EKSYaml = true
+}
+
 func TestConfigMap(t *testing.T) {
 	log.Level = logrus.DebugLevel
 
@@ -56,16 +61,6 @@ func TestConfigMap(t *testing.T) {
 			// Valid aws-auth.yaml based on one in EKS documentation.
 			"aws-auth.yaml", validRoleMappings, validUserMappings, validAWSAccounts, false,
 		},
-		{
-			// RoLeArN instead of rolearn
-			// parsing succeeds, values are case-insensitive for compatibility with upstream
-			"aws-auth-crazy-case-keys.yaml", validRoleMappings, validUserMappings, validAWSAccounts, false,
-		},
-		{
-			// roleARN instead of rolearn
-			// parsing succeeds, values are case-insensitive for compatibility with upstream
-			"aws-auth-open-source-case-keys.yaml", validRoleMappings, validUserMappings, validAWSAccounts, false,
-		},
 		// Fail cases -- ideally, validation should reject these before they reach us
 		{
 			// mapusers instead of mapUsers
@@ -94,6 +89,26 @@ func TestConfigMap(t *testing.T) {
 			"aws-auth-missing-bar.yaml", nil, nil, nil, true,
 		},
 	}
+	if !EKSYaml {
+		tests = append(tests, []struct {
+			configMapYaml        string
+			expectedRoleMappings []config.RoleMapping
+			expectedUserMappings []config.UserMapping
+			expectedAWSAccounts  map[string]bool
+			expectCreateError    bool
+		}{
+			{
+				// RoLeArN instead of rolearn
+				// parsing succeeds, values are case-insensitive for compatibility with upstream
+				"aws-auth-crazy-case-keys.yaml", validRoleMappings, validUserMappings, validAWSAccounts, false,
+			},
+			{
+				// roleARN instead of rolearn
+				// parsing succeeds, values are case-insensitive for compatibility with upstream
+				"aws-auth-open-source-case-keys.yaml", validRoleMappings, validUserMappings, validAWSAccounts, false,
+			},
+		}...)
+	}
 
 	for _, tt := range tests {
 		t.Run(tt.configMapYaml, func(t *testing.T) {