CVE-2021-29531

{"id": "CVE-2021-29531", "metrics": {"cvssMetricV2": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"version": "2.0", "baseScore": 2.1, "accessVector": "LOCAL", "vectorString": "AV:L/AC:L/Au:N/C:N/I:N/A:P", "authentication": "NONE", "integrityImpact": "NONE", "accessComplexity": "LOW", "availabilityImpact": "PARTIAL", "confidentialityImpact": "NONE"}, "acInsufInfo": false, "impactScore": 2.9, "baseSeverity": "LOW", "obtainAllPrivilege": false, "exploitabilityScore": 3.9, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}], "cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.8}, {"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 2.5, "attackVector": "LOCAL", "baseSeverity": "LOW", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "LOW", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 1.4, "exploitabilityScore": 1.0}]}, "published": "2021-05-14T20:15:12.027", "references": [{"url": "https://github.com/tensorflow/tensorflow/commit/26eb323554ffccd173e8a79a8c05c15b685ae4d1", "tags": ["Patch", "Third Party Advisory"], "source": "security-advisories@github.com"}, {"url": "https://github.com/tensorflow/tensorflow/security/advisories/GHSA-3qxp-qjq7-w4hf", "tags": ["Exploit", "Patch", "Third Party Advisory"], "source": "security-advisories@github.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-754"}]}], "descriptions": [{"lang": "en", "value": "TensorFlow is an end-to-end open source platform for machine learning. An attacker can trigger a `CHECK` fail in PNG encoding by providing an empty input tensor as the pixel data. This is because the implementation(https://github.com/tensorflow/tensorflow/blob/e312e0791ce486a80c9d23110841525c6f7c3289/tensorflow/core/kernels/image/encode_png_op.cc#L57-L60) only validates that the total number of pixels in the image does not overflow. Thus, an attacker can send an empty matrix for encoding. However, if the tensor is empty, then the associated buffer is `nullptr`. Hence, when calling `png::WriteImageToBuffer`(https://github.com/tensorflow/tensorflow/blob/e312e0791ce486a80c9d23110841525c6f7c3289/tensorflow/core/kernels/image/encode_png_op.cc#L79-L93), the first argument (i.e., `image.flat<T>().data()`) is `NULL`. This then triggers the `CHECK_NOTNULL` in the first line of `png::WriteImageToBuffer`(https://github.com/tensorflow/tensorflow/blob/e312e0791ce486a80c9d23110841525c6f7c3289/tensorflow/core/lib/png/png_io.cc#L345-L349). Since `image` is null, this results in `abort` being called after printing the stacktrace. Effectively, this allows an attacker to mount a denial of service attack. 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."}, {"lang": "es", "value": "TensorFlow es una plataforma de c\u00f3digo abierto de extremo a extremo para el aprendizaje autom\u00e1tico.&#xa0;Un atacante puede desencadenar \"CHECK\" en una codificaci\u00f3n PNG al proporcionar un tensor de entrada vac\u00edo como datos de p\u00edxeles.&#xa0;Esto es debido a que la implementaci\u00f3n (https://github.com/tensorflow/tensorflow/blob/e312e0791ce486a80c9d23110841525c6f7c3289/tensorflow/core/kernels/image/encode_png_op.cc#L57-L60) solo comprueba que el n\u00famero total de p\u00edxeles en una imagen no se desborda.&#xa0;Por lo tanto, un atacante puede enviar una matriz vac\u00eda para codificar.&#xa0;Sin embargo, si el tensor est\u00e1 vac\u00edo, entonces el b\u00fafer asociado es \"nullptr\".&#xa0;Por lo tanto, al llamar a la funci\u00f3n \"png::WriteImageToBuffer\" (https://github.com/tensorflow/tensorflow/blob/e312e0791ce486a80c9d23110841525c6f7c3289/tensorflow/core/kernels/image/encode_png_op.cc#L79-L93), el primer argumento (es decir, \"image.flat (T) () .data ()\") es \"NULL\".&#xa0;Esto luego desencadena el \"CHECK_NOTNULL\" en una primera l\u00ednea de la funci\u00f3n \"png::WriteImageToBuffer\" (https://github.com/tensorflow/tensorflow/blob/e312e0791ce486a80c9d23110841525c6f7c3289/tensorflow/core/lib/png/png_45-Lcc349L).&#xa0;Dado que \"image\" es null, esto resulta en que se llame a \"abort\" despu\u00e9s de imprimir el stacktrace.&#xa0;Efectivamente, esto permite a un atacante montar un ataque de denegaci\u00f3n de servicio.&#xa0;La correcci\u00f3n ser\u00e1 incluida en TensorFlow versi\u00f3n 2.5.0.&#xa0;Tambi\u00e9n seleccionaremos este commit en TensorFlow versi\u00f3n 2.4.2, TensorFlow versi\u00f3n 2.3.3, TensorFlow versi\u00f3n 2.2.3 y TensorFlow versi\u00f3n 2.1.4, ya que estos tambi\u00e9n est\u00e1n afectados y a\u00fan est\u00e1n en el rango compatible"}], "lastModified": "2021-05-20T15:46:57.893", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "323ABCCE-24EB-47CC-87F6-48C101477587", "versionEndExcluding": "2.1.4"}, {"criteria": "cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "64ABA90C-0649-4BB0-89C9-83C14BBDCC0F", "versionEndExcluding": "2.2.3", "versionStartIncluding": "2.2.0"}, {"criteria": "cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0F83E0CF-CBF6-4C24-8683-3E7A5DC95BA9", "versionEndExcluding": "2.3.3", "versionStartIncluding": "2.3.0"}, {"criteria": "cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "8259531B-A8AC-4F8B-B60F-B69DE4767C03", "versionEndExcluding": "2.4.2", "versionStartIncluding": "2.4.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}