CVE-2021-29572

TensorFlow SdcaOptimizer null pointer dereference

• CVSS 5.5
• CWE-476 NULL Pointer Dereference
• Cryptographic
• Remote

TensorFlow is an end-to-end open source platform for machine learning. The implementation of `tf.raw_ops.SdcaOptimizer` triggers undefined behavior due to dereferencing a null pointer. The implementation(https://github.com/tensorflow/tensorflow/blob/60a45c8b6192a4699f2e2709a2645a751d435cc3/tensorflow/core/kernels/sdca_internal.cc) does not validate that the user supplied arguments satisfy all constraints expected by the op(https://www.tensorflow.org/api_docs/python/tf/raw_ops/SdcaOptimizer). The fix will be included in TensorFlow 2.5.0. We will also cherrypick this commit on TensorFlow 2.4.2, TensorFlow 2.3.3, TensorFlow 2.2.3 and TensorFlow 2.1.4, as these are also affected and still in supported range.

CVE

CVE-2021-29572

CWE

CWE-476 NULL Pointer Dereference

CVSS base score

5.5

Published

2021-05-14

OWASP

A06 Vulnerable and Outdated Components

Orthogonal defect classification

Function

Code defect classification

Incorrect Functionality

Category

Cryptographic

Subcategory

Unencrypted communication

Accessibility scope

Remote

Impact

Denial of Service (DoS)

Affected component

TensorFlow

Fixed by upgrading

Yes

Solution

Update TensorFlow to version 2.5.0 or higher.

import tensorflow as tf

def sdca_optimizer():
    # VULNERABLE: This code is susceptible to command injection

    try:
        optimizer = tf.raw_ops.SdcaOptimizer(
            sparse_example_indices=[],
            sparse_feature_indices=[],
            sparse_feature_values=[],
            dense_features=[],
            example_weights=[],
            example_labels=[],
            sparse_indices=[],
            sparse_weights=[],
            dense_weights=[],
            example_state_data=[],
            loss_type="logistic_loss",
            l1=0.01,
            l2=0.01,
            num_loss_partitions=1,
            num_inner_iterations=1,
            dual_coefficients=None,  
            primal_loss=None  
        )
        print("Executed function without crash")
    except Exception as e:
        print(f"TensorFlow Error: {e}")

sdca_optimizer()

import tensorflow as tf

def sdca_optimizer():
    # SECURE: This version prevents command injection

    try:
        optimizer = tf.raw_ops.SdcaOptimizer(
            sparse_example_indices=[],
            sparse_feature_indices=[],
            sparse_feature_values=[],
            dense_features=[],
            example_weights=[],
            example_labels=[],
            sparse_indices=[],
            sparse_weights=[],
            dense_weights=[],
            example_state_data=[],
            loss_type="logistic_loss",
            l1=0.01,
            l2=0.01,
            num_loss_partitions=1,
            num_inner_iterations=1,
            dual_coefficients=[],
            primal_loss=[]
        )
        print("Executed function successfully")
    except Exception as e:
        print(f"TensorFlow Error: {e}")

sdca_optimizer()

@misc{vaitp:cve202129572,
  title        = {{TensorFlow SdcaOptimizer null pointer dereference}},
  author       = {Bogaerts, Fr\'ed\'eric and Ivaki, Naghmeh and Fonseca, Jos\'e},
  year         = {2021},
  note         = {VAITP Python Vulnerability Dataset, entry CVE-2021-29572},
  howpublished = {\url{https://netpack.pt/vaitp/vulnerability/CVE-2021-29572/}}
}