diff --git a/internal/web/oauth/callback.go b/internal/web/oauth/callback.go
index 3c217b2..baf21bd 100644
--- a/internal/web/oauth/callback.go
+++ b/internal/web/oauth/callback.go
@@ -2,11 +2,11 @@ package oauth
 
 import (
 	"context"
+	"fmt"
 	userApi "git.0x7f.app/WOJ/woj-server/internal/api/user"
 	"git.0x7f.app/WOJ/woj-server/internal/e"
 	"git.0x7f.app/WOJ/woj-server/internal/model"
 	"git.0x7f.app/WOJ/woj-server/internal/service/user"
-	"git.0x7f.app/WOJ/woj-server/pkg/utils"
 	"github.com/gin-gonic/gin"
 )
 
@@ -20,15 +20,27 @@ func (s *service) CallbackHandler() gin.HandlerFunc {
 	// TODO: we are returning e.Response directly here, we should redirect to a trampoline page, passing the response as query string
 
 	return func(c *gin.Context) {
-		// verify state
-		signed, err := c.Cookie(oauthStateCookieName)
+		// Extract key from cookie
+		key, err := c.Cookie(oauthStateCookieName)
 		if err != nil {
 			e.Pong[any](c, e.InvalidParameter, nil)
 			return
 		}
 
-		state := c.Query("state")
-		if !utils.SignAndCompare(state, signed, []byte(s.conf.ClientSecret)) {
+		// Get state from redis
+		key = fmt.Sprintf(oauthStateKey, key)
+		expected, err := s.cache.Get().Get(context.Background(), key).Result()
+		if err != nil {
+			e.Pong[any](c, e.RedisError, nil)
+			return
+		}
+
+		// Whether state is valid, delete it
+		s.cache.Get().Unlink(context.Background(), key)
+		c.SetCookie(oauthStateCookieName, "", -1, "/", "", false, true)
+
+		// Verify state
+		if c.Query("state") != expected {
 			e.Pong[any](c, e.OAuthStateMismatch, nil)
 			return
 		}
@@ -72,21 +84,21 @@ func (s *service) CallbackHandler() gin.HandlerFunc {
 			return
 		}
 
-		// Check User Existence
+		// Check user existence
 		u, status := s.user.ProfileOrCreate(&user.CreateData{UserName: claims.Email, NickName: claims.Nickname})
 		if status != e.Success {
 			e.Pong[any](c, status, nil)
 			return
 		}
 
-		// Increment User Version
+		// Increment user version
 		version, status := s.user.IncrVersion(u.ID)
 		if status != e.Success {
 			e.Pong[any](c, status, nil)
 			return
 		}
 
-		// Sign JWT Token
+		// Sign JWT token
 		claim := &model.Claim{
 			UID:     u.ID,
 			Role:    u.Role,
diff --git a/internal/web/oauth/login.go b/internal/web/oauth/login.go
index 44bfeed..4eb9917 100644
--- a/internal/web/oauth/login.go
+++ b/internal/web/oauth/login.go
@@ -1,14 +1,18 @@
 package oauth
 
 import (
+	"context"
+	"fmt"
 	"git.0x7f.app/WOJ/woj-server/internal/e"
 	"git.0x7f.app/WOJ/woj-server/pkg/utils"
 	"github.com/gin-gonic/gin"
 	"net/http"
+	"time"
 )
 
 const (
 	oauthStateCookieName = "oauth_state"
+	oauthStateKey        = "OAuthState:%s"
 )
 
 // LoginHandler
@@ -21,12 +25,18 @@ const (
 func (s *service) LoginHandler() gin.HandlerFunc {
 	return func(c *gin.Context) {
 		state := utils.RandomString(64)
-		signed := utils.SignString(state, []byte(s.conf.ClientSecret))
-		url := s.conf.AuthCodeURL(state)
+		key := utils.RandomString(16)
+
+		err := s.cache.Get().Set(context.Background(), fmt.Sprintf(oauthStateKey, key), state, 15*time.Minute).Err()
+		if err != nil {
+			e.Pong[any](c, e.RedisError, nil)
+			return
+		}
 
 		c.SetSameSite(http.SameSiteStrictMode)
-		c.SetCookie(oauthStateCookieName, signed, 15*60, "/", "", false, true)
+		c.SetCookie(oauthStateCookieName, key, 15*60, "/", "", false, true)
 
+		url := s.conf.AuthCodeURL(state)
 		e.Pong(c, e.Success, url)
 	}
 }
diff --git a/internal/web/oauth/service.go b/internal/web/oauth/service.go
index b83f142..48e2d90 100644
--- a/internal/web/oauth/service.go
+++ b/internal/web/oauth/service.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"git.0x7f.app/WOJ/woj-server/internal/misc/config"
 	"git.0x7f.app/WOJ/woj-server/internal/misc/log"
+	"git.0x7f.app/WOJ/woj-server/internal/repo/cache"
 	"git.0x7f.app/WOJ/woj-server/internal/service/user"
 	"git.0x7f.app/WOJ/woj-server/internal/web/jwt"
 	"github.com/coreos/go-oidc/v3/oidc"
@@ -34,6 +35,7 @@ func NewService(i *do.Injector) (Service, error) {
 	srv.log = do.MustInvoke[log.Service](i).GetLogger("oauth")
 	srv.jwt = do.MustInvoke[jwt.Service](i)
 	srv.user = do.MustInvoke[user.Service](i)
+	srv.cache = do.MustInvoke[cache.Service](i)
 	srv.enabled = false
 
 	conf := do.MustInvoke[config.Service](i).GetConfig()
@@ -63,9 +65,10 @@ func NewService(i *do.Injector) (Service, error) {
 }
 
 type service struct {
-	log  *zap.Logger
-	jwt  jwt.Service
-	user user.Service
+	log   *zap.Logger
+	jwt   jwt.Service
+	user  user.Service
+	cache cache.Service
 
 	provider *oidc.Provider
 	conf     oauth2.Config