diff --git a/requirements.txt b/requirements.txt
index cdd72e16..92dec7ba 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,6 +4,6 @@ cryptography==45.0.5
 ecdsa==0.19.1
 googleapis-common-protos==1.70.0
 grpcio==1.73.1
-protobuf==6.31.1
+protobuf==5.29.6
 pycparser==2.22
 toml==0.10.2
diff --git a/requirements_dev.txt b/requirements_dev.txt
index 8f560879..09291aca 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -27,7 +27,7 @@ mypy==1.16.1
 packaging==25.0
 pkginfo==1.12.1.2
 pluggy==1.6.0
-protobuf==6.31.1
+protobuf==5.29.6
 pycodestyle==2.14.0
 pyflakes==3.4.0
 pygments==2.19.2