CVE-2021-37685: Heap OOB in TensorFlow Lite
Impact TFLite's expanddims.cc contains a vulnerability which allows reading one element outside of bounds of heap allocated data:
cc if (axis < 0) { axis = inputdims.size + 1 + axis; } TFLITEENSURE(context, axis <= inputdims.size);
TfLiteIntArray outputdims = TfLiteIntArrayCreate(inputdims.size + 1); for (int i = 0; i < outputdims->size; ++i) { if (i < axis) { outputdims->data[i] = inputdims.data[i]; } else if (i == axis) { outputdims->data[i] = 1; } else { outputdims->data[i] = inputdims.data[i - 1]; } }
If axis is a large negative value (e.g., -100000), then after the first if it would still be negative. The check following the if statement will pass and the for loop would read one element before the start of inputdims.data (when i = 0).
Patches We have patched the issue in GitHub commit d94ffe08a65400f898241c0374e9edc6fa8ed257.
The fix will be included in TensorFlow 2.6.0. We will also cherrypick this commit on TensorFlow 2.5.1, TensorFlow 2.4.3, and TensorFlow 2.3.4, as these are also affected and still in supported range.
For more information Please consult our security guide for more information regarding the security model and how to contact us with issues and questions.
Attribution This vulnerability has been reported by Yakun Zhang of Baidu Security.
Other sources
TensorFlow is an end-to-end open source platform for machine learning. In affected versions TFLite's expanddims.cc contains a vulnerability which allows reading one element outside of bounds of heap allocated data. If axis is a large negative value (e.g., -100000), then after the first if it would still be negative. The check following the if statement will pass and the for loop would read one element before the start of inputdims.data (when i = 0). We have patched the issue in GitHub commit d94ffe08a65400f898241c0374e9edc6fa8ed257. The fix will be included in TensorFlow 2.6.0. We will also cherrypick this commit on TensorFlow 2.5.1, TensorFlow 2.4.3, and TensorFlow 2.3.4, as these are also affected and still in supported range.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
pip/tensorflow-gputo a version that resolves this vulnerability.Fixed in 2.5.1 - Upgrade
Upgrade
pip/tensorflow-gputo a version that resolves this vulnerability.Fixed in 2.4.3 - Upgrade
Upgrade
pip/tensorflow-gputo a version that resolves this vulnerability.Fixed in 2.3.4 - Upgrade
Upgrade
pip/tensorflow-cputo a version that resolves this vulnerability.Fixed in 2.5.1 - Upgrade
Upgrade
pip/tensorflow-cputo a version that resolves this vulnerability.Fixed in 2.4.3 - Upgrade
Upgrade
pip/tensorflow-cputo a version that resolves this vulnerability.Fixed in 2.3.4 - Upgrade
Upgrade
pip/tensorflowto a version that resolves this vulnerability.Fixed in 2.5.1 - Upgrade
Upgrade
pip/tensorflowto a version that resolves this vulnerability.Fixed in 2.4.3 - Upgrade
Upgrade
pip/tensorflowto a version that resolves this vulnerability.Fixed in 2.3.4 - Upgrade
Upgrade
TensorFlowto a version that resolves this vulnerability.Fixed in 2.6.0Patch d94ffe08a65400f898241c0374e9edc6fa8ed257 - Upgrade
Upgrade
TensorFlowto a version that resolves this vulnerability.Fixed in 2.5.1Patch d94ffe08a65400f898241c0374e9edc6fa8ed257 - Upgrade
Upgrade
TensorFlowto a version that resolves this vulnerability.Fixed in 2.4.3Patch d94ffe08a65400f898241c0374e9edc6fa8ed257 - Upgrade
Upgrade
TensorFlowto a version that resolves this vulnerability.Fixed in 2.3.4Patch d94ffe08a65400f898241c0374e9edc6fa8ed257
Event History
Frequently Asked Questions
What is the severity of CVE-2021-37685?
CVE-2021-37685 has a high severity level due to the potential for out-of-bounds memory access.
How do I fix CVE-2021-37685?
To fix CVE-2021-37685, upgrade to TensorFlow version 2.5.1 or later.
Which versions of TensorFlow are affected by CVE-2021-37685?
CVE-2021-37685 affects TensorFlow versions 2.3.0 to 2.3.4, 2.4.0 to 2.4.3, and specific 2.6.0 release candidates.
What type of vulnerability is CVE-2021-37685?
CVE-2021-37685 is an out-of-bounds read vulnerability that can lead to unauthorized data access.
Can CVE-2021-37685 be exploited remotely?
CVE-2021-37685 may be exploitable remotely, depending on how TensorFlow is used in an application.