From 3cd9ceec33ced359decbad75b413ad668ae6332c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Jos=C3=A9=20Padilla?= Date: Fri, 11 Sep 2026 22:29:12 -0400 Subject: [PATCH] fix: reject inconsistent OKP private keys --- jwt/algorithms.py | 14 ++++++++++++-- tests/test_algorithms.py | 29 +++++++++++++++++++++++++++++ 2 files changed, 41 insertions(+), 2 deletions(-) Index: pyjwt-2.12.1/jwt/algorithms.py =================================================================== --- pyjwt-2.12.1.orig/jwt/algorithms.py +++ pyjwt-2.12.1/jwt/algorithms.py @@ -1039,8 +1039,18 @@ if has_crypto: return Ed25519PublicKey.from_public_bytes(x) return Ed448PublicKey.from_public_bytes(x) d = base64url_decode(obj.get("d")) + private_key: Ed25519PrivateKey | Ed448PrivateKey if curve == "Ed25519": - return Ed25519PrivateKey.from_private_bytes(d) - return Ed448PrivateKey.from_private_bytes(d) + private_key = Ed25519PrivateKey.from_private_bytes(d) + else: + private_key = Ed448PrivateKey.from_private_bytes(d) + if ( + private_key.public_key().public_bytes( + encoding=Encoding.Raw, format=PublicFormat.Raw + ) + != x + ): + raise InvalidKeyError("Public key does not match private key") + return private_key except ValueError as err: raise InvalidKeyError("Invalid key parameter") from err Index: pyjwt-2.12.1/tests/test_algorithms.py =================================================================== --- pyjwt-2.12.1.orig/tests/test_algorithms.py +++ pyjwt-2.12.1/tests/test_algorithms.py @@ -942,6 +942,35 @@ class TestAlgorithmsRFC7520: @crypto_required class TestOKPAlgorithms: + @pytest.mark.parametrize("curve", ("Ed25519", "Ed448")) + @pytest.mark.parametrize("as_dict", (False, True)) + def test_okp_jwk_should_reject_inconsistent_private_key( + self, curve: str, as_dict: bool + ) -> None: + with open(key_path(f"jwk_okp_key_{curve}.json")) as keyfile: + jwk = json.load(keyfile) + + d = base64url_decode(jwk["d"]) + jwk["d"] = ( + base64.urlsafe_b64encode(bytes([d[0] ^ 1]) + d[1:]).rstrip(b"=").decode() + ) + + with pytest.raises(InvalidKeyError): + OKPAlgorithm.from_jwk(jwk if as_dict else json.dumps(jwk)) + + @pytest.mark.parametrize("curve", ("Ed25519", "Ed448")) + @pytest.mark.parametrize("length", (0, 1, 56, 58)) + def test_okp_jwk_should_reject_private_key_with_invalid_public_length( + self, curve: str, length: int + ) -> None: + with open(key_path(f"jwk_okp_key_{curve}.json")) as keyfile: + jwk = json.load(keyfile) + + jwk["x"] = base64.urlsafe_b64encode(b"\x00" * length).rstrip(b"=").decode() + + with pytest.raises(InvalidKeyError): + OKPAlgorithm.from_jwk(jwk) + hello_world_sig = b"Qxa47mk/azzUgmY2StAOguAd4P7YBLpyCfU3JdbaiWnXM4o4WibXwmIHvNYgN3frtE2fcyd8OYEaOiD/KiwkCg==" hello_world_sig_pem = b"9ueQE7PT8uudHIQb2zZZ7tB7k1X3jeTnIfOVvGCINZejrqQbru1EXPeuMlGcQEZrGkLVcfMmr99W/+byxfppAg==" hello_world = b"Hello World!"