CVE-2021-37639
August 12, 2021
TensorFlow is an end-to-end open source platform for machine learning. When restoring tensors via raw APIs, if the tensor name is not provided, TensorFlow can be tricked into dereferencing a null pointer. Alternatively, attackers can read memory outside the bounds of heap allocated data by providing some tensor names but not enough for a successful restoration. The [implementation](https://github.com/tensorflow/tensorflow/blob/47a06f40411a69c99f381495f490536972152ac0/tensorflow/core/kernels/save_restore_tensor.cc#L158-L159) retrieves the tensor list corresponding to the `tensor_name` user controlled input and immediately retrieves the tensor at the restoration index (controlled via `preferred_shard` argument). This occurs without validating that the provided list has enough values. If the list is empty this results in dereferencing a null pointer (undefined behavior). If, however, the list has some elements, if the restoration index is outside the bounds this results in heap OOB read. We have patched the issue in GitHub commit 9e82dce6e6bd1f36a57e08fa85af213e2b2f2622. 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 Packages
tensorflow (PYTHON):
Affected version(s) >=0.11.0rc2 <2.3.4Fix Suggestion:
Update to version 2.3.4tensorflow-cpu (PYTHON):
Affected version(s) =2.5.0 <2.5.1Fix Suggestion:
Update to version 2.5.1tensorflow-gpu (PYTHON):
Affected version(s) >=2.4.0 <2.4.3Fix Suggestion:
Update to version 2.4.3tensorflow-cpu (PYTHON):
Affected version(s) >=2.4.0 <2.4.3Fix Suggestion:
Update to version 2.4.3tensorflow-gpu (PYTHON):
Affected version(s) =2.5.0 <2.5.1Fix Suggestion:
Update to version 2.5.1tensorflow (PYTHON):
Affected version(s) >=2.4.0 <2.4.3Fix Suggestion:
Update to version 2.4.3tensorflow (PYTHON):
Affected version(s) =2.5.0 <2.5.1Fix Suggestion:
Update to version 2.5.1tensorflow-gpu (PYTHON):
Affected version(s) >=0.12.0rc0 <2.3.4Fix Suggestion:
Update to version 2.3.4tensorflow-cpu (PYTHON):
Affected version(s) >=0.0.0 <2.3.4Fix Suggestion:
Update to version 2.3.4Additional Notes
The description of this vulnerability differs from MITRE.
Related Resources (7)
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Contact UsCVSS v4
Base Score:
8.6
Attack Vector
LOCAL
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
8.4
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
CVSS v2
Base Score:
4.6
Access Vector
LOCAL
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
EPSS
Base Score:
0.01