{"id":"CVE-2021-37640","aliases":["BIT-tensorflow-2021-37640","GHSA-95xm-g58g-3p88","PYSEC-2021-262","PYSEC-2021-553","PYSEC-2021-751"],"url":"https://o3.security/vulnerability/CVE-2021-37640","summary":"Integer division by 0 in sparse reshaping","details":"### Impact\nThe implementation of `tf.raw_ops.SparseReshape` can be made to trigger an integral division by 0 exception:\n\n```python\nimport tensorflow as tf\n\ntf.raw_ops.SparseReshape(\n  input_indices = np.ones((1,3)),\n  input_shape = np.array([1,1,0]),\n  new_shape = np.array([1,0]))\n```\n  \nThe [implementation](https://github.com/tensorflow/tensorflow/blob/8d72537c6abf5a44103b57b9c2e22c14f5f49698/tensorflow/core/kernels/reshape_util.cc#L176-L181) calls the reshaping functor whenever there is at least an index in the input but does not check that shape of the input or the target shape have both a non-zero number of elements.\n\nThe [reshape functor](https://github.com/tensorflow/tensorflow/blob/8d72537c6abf5a44103b57b9c2e22c14f5f49698/tensorflow/core/kernels/reshape_util.cc#L40-L78) blindly divides by the dimensions of the target shape. Hence, if this is not checked, code will result in a division by 0.\n  \n### Patches\nWe have patched the issue in GitHub commit [4923de56ec94fff7770df259ab7f2288a74feb41](https://github.com/tensorflow/tensorflow/commit/4923de56ec94fff7770df259ab7f2288a74feb41).\n\nThe fix will be included in TensorFlow 2.6.0. We will also cherrypick this commit on TensorFlow 2.5.1 as this is the other affected version.\n\n### For more information\nPlease consult [our security guide](https://github.com/tensorflow/tensorflow/blob/master/SECURITY.md) for more information regarding the security model and how to contact us with issues and questions.\n  \n### Attribution\nThis vulnerability has been reported by members of the Aivul Team from Qihoo 360.","published":"2021-08-12T18:15:10.490Z","modified":"2026-08-07T17:02:27.337108Z","cvss":{"score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"tensorflow","fixedVersion":"2.3.4"},{"ecosystem":"PyPI","name":"tensorflow","fixedVersion":"2.4.3"},{"ecosystem":"PyPI","name":"tensorflow","fixedVersion":"2.5.1"},{"ecosystem":"PyPI","name":"tensorflow-cpu","fixedVersion":"2.3.4"},{"ecosystem":"PyPI","name":"tensorflow-cpu","fixedVersion":"2.4.3"},{"ecosystem":"PyPI","name":"tensorflow-cpu","fixedVersion":"2.5.1"},{"ecosystem":"PyPI","name":"tensorflow-gpu","fixedVersion":"2.3.4"},{"ecosystem":"PyPI","name":"tensorflow-gpu","fixedVersion":"2.4.3"},{"ecosystem":"PyPI","name":"tensorflow-gpu","fixedVersion":"2.5.1"}],"fix":{"url":"https://github.com/tensorflow/tensorflow/commit/4923de56ec94fff7770df259ab7f2288a74feb41","label":"tensorflow/tensorflow@4923de5"},"references":[{"type":"ADVISORY","url":"https://github.com/tensorflow/tensorflow/security/advisories/GHSA-95xm-g58g-3p88"},{"type":"FIX","url":"https://github.com/tensorflow/tensorflow/commit/4923de56ec94fff7770df259ab7f2288a74feb41"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-37640"},{"type":"WEB","url":"https://github.com/pypa/advisory-database/tree/main/vulns/tensorflow-cpu/PYSEC-2021-553.yaml"},{"type":"WEB","url":"https://github.com/pypa/advisory-database/tree/main/vulns/tensorflow-gpu/PYSEC-2021-751.yaml"},{"type":"WEB","url":"https://github.com/pypa/advisory-database/tree/main/vulns/tensorflow/PYSEC-2021-262.yaml"},{"type":"PACKAGE","url":"https://github.com/tensorflow/tensorflow"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T17:02:27.337108Z"}}