diff --git a/requirements/build.txt b/requirements/build.txt
index 994635309..6c6c9fc8a 100644
--- a/requirements/build.txt
+++ b/requirements/build.txt
@@ -9,5 +9,5 @@ wheel
 jinja2>=3.1.6
 regex
 build
-protobuf
+protobuf >= 5.29.6, !=6.30.*, !=6.31.*, !=6.32.*, !=6.33.0.*, !=6.33.1.*, !=6.33.2.*, !=6.33.3.*, !=6.33.4.*
 grpcio-tools==1.78.0 # Required for grpc entrypoints
diff --git a/requirements/common.txt b/requirements/common.txt
index f8402410b..297447cf2 100644
--- a/requirements/common.txt
+++ b/requirements/common.txt
@@ -9,7 +9,7 @@ blake3
 py-cpuinfo
 transformers >= 4.56.0, < 5
 tokenizers >= 0.21.1  # Required for fast incremental detokenization.
-protobuf # Required by LlamaTokenizer, gRPC.
+protobuf >= 5.29.6, !=6.30.*, !=6.31.*, !=6.32.*, !=6.33.0.*, !=6.33.1.*, !=6.33.2.*, !=6.33.3.*, !=6.33.4.* # Required by LlamaTokenizer, gRPC. CVE-2026-0994
 fastapi[standard] >= 0.115.0 # Required by FastAPI's form models in the OpenAI API server's audio transcriptions endpoint.
 aiohttp >= 3.13.3
 openai >= 1.99.1  # For Responses API with reasoning content