Security advisory

{
  "id": "8963cd60a11c9982a9a01c4d3b791ad9ff6fe4ec03feab00c4c9d8931d4c646b",
  "url": "https://osv.dev/vulnerability/CVE-2021-29543",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2021-29543",
    "summary": "TensorFlow is an end-to-end open source platform for machine learning. An attacker can trigger a denial of service via a `CHECK`-fail in `tf.raw_ops.CTCGreedyDecoder`. This is because the implementation(https://github.com/tensorflow/tensorflow/blob/1615440b17b364b875eb06f43d087381f1460a65/tensorflow/core/kernels/ctc_decoder_ops.cc#L37-L50) has a `CHECK_LT` inserted to validate some invariants. When this condition is false, the program aborts, instead of returning a valid error to the user. This abnormal termination can be weaponized in denial of service attacks. 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.",
    "evidence": "osv:CVE-2021-29543",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2021-29543",
      "aliases": [
        "BIT-tensorflow-2021-29543",
        "CVE-2021-29543",
        "GHSA-fphq-gw9m-ghrv",
        "PYSEC-2021-180",
        "PYSEC-2021-471",
        "PYSEC-2021-669"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/tensorflow/tensorflow",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "0931ea3d985bb9c8fdd054a5e29c4129623c849b"
                },
                {
                  "introduced": "2b96f3662bd776e277f86997659e61046b56c315"
                },
                {
                  "fixed": "cfe0c80169ae984bcdc99ff6de7444164aaa8e07"
                },
                {
                  "introduced": "b36436b087bd8e8701ef51718179037cccdfc26e"
                },
                {
                  "fixed": "3929ffacfbef7c431e8397920d040aaf47acff19"
                },
                {
                  "introduced": "582c8d236cb079023657287c318ff26adb239002"
                },
                {
                  "fixed": "1923123d32ea41d92b70a27a3f6ecf0763b56f6c"
                },
                {
                  "fixed": "ea3b43e98c32c97b35d52b4c66f9107452ca8fb2"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "2.1.4"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "2.2.0"
                      },
                      {
                        "fixed": "2.2.3"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "2.3.0"
                      },
                      {
                        "fixed": "2.3.3"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "2.4.0"
                      },
                      {
                        "fixed": "2.4.2"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "ea3b43e98c32c97b35d52b4c66f9107452ca8fb2"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v2.1.3",
            "v2.2.2",
            "v2.3.2",
            "v2.4.1",
            "v2.1.2",
            "v2.2.1",
            "v2.4.0",
            "v2.3.1",
            "v2.2.0",
            "v2.1.1",
            "v2.3.0",
            "v2.1.0",
            "v2.1.0-rc0",
            "v2.1.0-rc2",
            "v2.1.0-rc1",
            "v1.12.1",
            "v1.9.0-rc2",
            "v1.6.0-rc1",
            "v1.1.0-rc2",
            "v1.1.0-rc1",
            "0.6.0",
            "0.5.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-29543.json",
            "vanir_signatures": [
              {
                "id": "CVE-2021-29543-02d604b5",
                "digest": {
                  "threshold": 0.9,
                  "line_hashes": [
                    "318415061227392128622842619183911306269",
                    "7083256035842637460101706698118416224",
                    "117765765445815321662557144378622521920",
                    "304321014125267941886832379736815343616"
                  ]
                },
                "source": "https://github.com/tensorflow/tensorflow/commit/ea3b43e98c32c97b35d52b4c66f9107452ca8fb2",
                "target": {
                  "file": "tensorflow/core/kernels/ctc_decoder_ops.cc"
                },
                "deprecated": false,
                "signature_type": "Line",
                "signature_version": "v1"
              }
            ],
            "vanir_signatures_modified": "2026-10-20T14:24:27Z"
          }
        }
      ],
      "modified": "2026-10-20T14:24:27.958978367Z",
      "provider": "osv",
      "references": [
        "https://github.com/tensorflow/tensorflow/commit/ea3b43e98c32c97b35d52b4c66f9107452ca8fb2",
        "https://github.com/tensorflow/tensorflow/security/advisories/GHSA-fphq-gw9m-ghrv"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2021-29543",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 388914,
  "published_at": "2021-05-14T20:15:12.577+00:00"
}