diff --git a/mcp/agent/requirements.txt b/mcp/agent/requirements.txt
index 64c7c5b969b..31c81d9bc10 100644
--- a/mcp/agent/requirements.txt
+++ b/mcp/agent/requirements.txt
@@ -134,9 +134,9 @@ attrs==25.3.0 \
     #   aiohttp
     #   jsonschema
     #   referencing
-authlib==1.6.3 \
-    --hash=sha256:7ea0f082edd95a03b7b72edac65ec7f8f68d703017d7e37573aee4fc603f2a48 \
-    --hash=sha256:9f7a982cc395de719e4c2215c5707e7ea690ecf84f1ab126f28c053f4219e610
+authlib==1.6.4 \
+    --hash=sha256:104b0442a43061dc8bc23b133d1d06a2b0a9c2e3e33f34c4338929e816287649 \
+    --hash=sha256:39313d2a2caac3ecf6d8f95fbebdfd30ae6ea6ae6a6db794d976405fdd9aa796
     # via google-adk
 cachetools==5.5.2 \
     --hash=sha256:1a661caa9175d26759571b2e19580f9d6393969e5dfca11fdb1f947a23e640d4 \