diff --git a/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/oidc/authentication/OidcLogoutAuthenticationProvider.java b/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/oidc/authentication/OidcLogoutAuthenticationProvider.java
index a40c7b07..3fa3c459 100644
--- a/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/oidc/authentication/OidcLogoutAuthenticationProvider.java
+++ b/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/oidc/authentication/OidcLogoutAuthenticationProvider.java
@@ -20,7 +20,6 @@ import java.util.List;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
-import org.springframework.security.authentication.AnonymousAuthenticationToken;
 import org.springframework.security.authentication.AuthenticationProvider;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.AuthenticationException;
@@ -109,7 +108,7 @@ public final class OidcLogoutAuthenticationProvider implements AuthenticationPro
 		}
 		if (StringUtils.hasText(oidcLogoutAuthentication.getClientId()) &&
 				!oidcLogoutAuthentication.getClientId().equals(registeredClient.getClientId())) {
-			throwError(OAuth2ErrorCodes.INVALID_TOKEN, OAuth2ParameterNames.CLIENT_ID);
+			throwError(OAuth2ErrorCodes.INVALID_REQUEST, OAuth2ParameterNames.CLIENT_ID);
 		}
 		if (StringUtils.hasText(oidcLogoutAuthentication.getPostLogoutRedirectUri()) &&
 				!registeredClient.getPostLogoutRedirectUris().contains(oidcLogoutAuthentication.getPostLogoutRedirectUri())) {
@@ -121,8 +120,8 @@ public final class OidcLogoutAuthenticationProvider implements AuthenticationPro
 		}
 
 		// Validate user identity
-		Authentication userPrincipal = (Authentication) oidcLogoutAuthentication.getPrincipal();
-		if (isPrincipalAuthenticated(userPrincipal)) {
+		if (oidcLogoutAuthentication.isPrincipalAuthenticated()) {
+			Authentication userPrincipal = (Authentication) oidcLogoutAuthentication.getPrincipal();
 			if (!StringUtils.hasText(idToken.getSubject()) ||
 					!idToken.getSubject().equals(userPrincipal.getName())) {
 				throwError(OAuth2ErrorCodes.INVALID_TOKEN, IdTokenClaimNames.SUB);
@@ -146,7 +145,7 @@ public final class OidcLogoutAuthenticationProvider implements AuthenticationPro
 			this.logger.trace("Authenticated logout request");
 		}
 
-		return new OidcLogoutAuthenticationToken(idToken, userPrincipal,
+		return new OidcLogoutAuthenticationToken(idToken, (Authentication) oidcLogoutAuthentication.getPrincipal(),
 				oidcLogoutAuthentication.getSessionId(), oidcLogoutAuthentication.getClientId(),
 				oidcLogoutAuthentication.getPostLogoutRedirectUri(), oidcLogoutAuthentication.getState());
 	}
@@ -156,12 +155,6 @@ public final class OidcLogoutAuthenticationProvider implements AuthenticationPro
 		return OidcLogoutAuthenticationToken.class.isAssignableFrom(authentication);
 	}
 
-	private static boolean isPrincipalAuthenticated(Authentication principal) {
-		return principal != null &&
-				!AnonymousAuthenticationToken.class.isAssignableFrom(principal.getClass()) &&
-				principal.isAuthenticated();
-	}
-
 	private SessionInformation findSessionInformation(Authentication principal, String sessionId) {
 		List<SessionInformation> sessions = this.sessionRegistry.getAllSessions(principal.getPrincipal(), true);
 		SessionInformation sessionInformation = null;
diff --git a/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/oidc/authentication/OidcLogoutAuthenticationToken.java b/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/oidc/authentication/OidcLogoutAuthenticationToken.java
index 5e3d0698..1e086c1b 100644
--- a/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/oidc/authentication/OidcLogoutAuthenticationToken.java
+++ b/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/oidc/authentication/OidcLogoutAuthenticationToken.java
@@ -19,6 +19,7 @@ import java.util.Collections;
 
 import org.springframework.lang.Nullable;
 import org.springframework.security.authentication.AbstractAuthenticationToken;
+import org.springframework.security.authentication.AnonymousAuthenticationToken;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.oauth2.core.oidc.OidcIdToken;
 import org.springframework.security.oauth2.server.authorization.util.SpringAuthorizationServerVersion;
@@ -102,6 +103,16 @@ public class OidcLogoutAuthenticationToken extends AbstractAuthenticationToken {
 		return this.principal;
 	}
 
+	/**
+	 * Returns {@code true} if {@link #getPrincipal()} is authenticated, {@code false} otherwise.
+	 *
+	 * @return {@code true} if {@link #getPrincipal()} is authenticated, {@code false} otherwise
+	 */
+	public boolean isPrincipalAuthenticated() {
+		return !AnonymousAuthenticationToken.class.isAssignableFrom(this.principal.getClass()) &&
+				this.principal.isAuthenticated();
+	}
+
 	@Override
 	public Object getCredentials() {
 		return "";
diff --git a/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/oidc/web/OidcLogoutEndpointFilter.java b/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/oidc/web/OidcLogoutEndpointFilter.java
index b0cc3eea..b2d102eb 100644
--- a/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/oidc/web/OidcLogoutEndpointFilter.java
+++ b/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/oidc/web/OidcLogoutEndpointFilter.java
@@ -26,7 +26,6 @@ import jakarta.servlet.http.HttpServletResponse;
 import org.springframework.core.log.LogMessage;
 import org.springframework.http.HttpMethod;
 import org.springframework.http.HttpStatus;
-import org.springframework.security.authentication.AnonymousAuthenticationToken;
 import org.springframework.security.authentication.AuthenticationManager;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.AuthenticationException;
@@ -183,7 +182,8 @@ public final class OidcLogoutEndpointFilter extends OncePerRequestFilter {
 		OidcLogoutAuthenticationToken oidcLogoutAuthentication = (OidcLogoutAuthenticationToken) authentication;
 
 		// Check for active user session
-		if (isSessionActive(oidcLogoutAuthentication)) {
+		if (oidcLogoutAuthentication.isPrincipalAuthenticated() &&
+				StringUtils.hasText(oidcLogoutAuthentication.getSessionId())) {
 			// Perform logout
 			this.logoutHandler.logout(request, response,
 					(Authentication) oidcLogoutAuthentication.getPrincipal());
@@ -216,15 +216,4 @@ public final class OidcLogoutEndpointFilter extends OncePerRequestFilter {
 		response.sendError(HttpStatus.BAD_REQUEST.value(), error.toString());
 	}
 
-	private static boolean isSessionActive(OidcLogoutAuthenticationToken oidcLogoutAuthentication) {
-		return isPrincipalAuthenticated((Authentication) oidcLogoutAuthentication.getPrincipal()) &&
-				StringUtils.hasText(oidcLogoutAuthentication.getSessionId());
-	}
-
-	private static boolean isPrincipalAuthenticated(Authentication principal) {
-		return principal != null &&
-				!AnonymousAuthenticationToken.class.isAssignableFrom(principal.getClass()) &&
-				principal.isAuthenticated();
-	}
-
 }
diff --git a/oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/server/authorization/oidc/authentication/OidcLogoutAuthenticationProviderTests.java b/oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/server/authorization/oidc/authentication/OidcLogoutAuthenticationProviderTests.java
index 4928f4c1..bcb00451 100644
--- a/oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/server/authorization/oidc/authentication/OidcLogoutAuthenticationProviderTests.java
+++ b/oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/server/authorization/oidc/authentication/OidcLogoutAuthenticationProviderTests.java
@@ -230,7 +230,7 @@ public class OidcLogoutAuthenticationProviderTests {
 				.isInstanceOf(OAuth2AuthenticationException.class)
 				.extracting(ex -> ((OAuth2AuthenticationException) ex).getError())
 				.satisfies(error -> {
-					assertThat(error.getErrorCode()).isEqualTo(OAuth2ErrorCodes.INVALID_TOKEN);
+					assertThat(error.getErrorCode()).isEqualTo(OAuth2ErrorCodes.INVALID_REQUEST);
 					assertThat(error.getDescription()).contains(OAuth2ParameterNames.CLIENT_ID);
 				});
 		verify(this.authorizationService).findByToken(