AVID-2026-R0749

Description

Null pointer dereference in StringNGrams (CVE-2021-29541)

Details

TensorFlow is an end-to-end open source platform for machine learning. An attacker can trigger a dereference of a null pointer in tf.raw_ops.StringNGrams. This is because the implementation(https://github.com/tensorflow/tensorflow/blob/1cdd4da14282210cc759e468d9781741ac7d01bf/tensorflow/core/kernels/string_ngrams_op.cc#L67-L74) does not fully validate the data_splits argument. This would result in ngrams_data(https://github.com/tensorflow/tensorflow/blob/1cdd4da14282210cc759e468d9781741ac7d01bf/tensorflow/core/kernels/string_ngrams_op.cc#L106-L110) to be a null pointer when the output would be computed to have 0 or negative size. Later writes to the output tensor would then cause a null pointer dereference. 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.

Reason for inclusion in AVID: CVE-2021-29541 describes a null pointer dereference in TensorFlow’s StringNGrams op, a vulnerability in a widely-used AI framework. It affects TensorFlow versions used in AI pipelines, representing a software supply chain issue in libraries used to build/train/serve AI systems. It is a security vulnerability (CWE-476) with local exploitation risk. The report includes CVE reference, description, affected artifacts, and a fix commit, providing sufficient evidence.

References

• NVD entry
• https://github.com/tensorflow/tensorflow/commit/ba424dd8f16f7110eea526a8086f1a155f14f22b
• https://github.com/tensorflow/tensorflow/security/advisories/GHSA-xqfj-35wv-m3cr

Affected or Relevant Artifacts

• Developer: tensorflow
• Deployer: tensorflow
• Artifact Details:

Impact

AVID Taxonomy Categorization

• Risk domains: Security
• SEP subcategories: S0100: Software Vulnerability
• Lifecycle stages: L06: Deployment

CVSS

CWE

Other information

• Report Type: Advisory
• Credits:
• Date Reported: 2021-05-14
• Version: 0.3.3
• AVID Entry