Upstream information
Description
In TensorFlow Lite before versions 1.15.4, 2.0.3, 2.1.2, 2.2.1 and 2.3.1, saved models in the flatbuffer format use a double indexing scheme: a model has a set of subgraphs, each subgraph has a set of operators and each operator has a set of input/output tensors. The flatbuffer format uses indices for the tensors, indexing into an array of tensors that is owned by the subgraph. This results in a pattern of double array indexing when trying to get the data of each tensor. However, some operators can have some tensors be optional. To handle this scenario, the flatbuffer model uses a negative `-1` value as index for these tensors. This results in special casing during validation at model loading time. Unfortunately, this means that the `-1` index is a valid tensor index for any operator, including those that don't expect optional inputs and including for output tensors. Thus, this allows writing and reading from outside the bounds of heap allocated arrays, although only at a specific offset from the start of these arrays. This results in both read and write gadgets, albeit very limited in scope. The issue is patched in several commits (46d5b0852, 00302787b7, e11f5558, cd31fd0ce, 1970c21, and fff2c83), and is released in TensorFlow versions 1.15.4, 2.0.3, 2.1.2, 2.2.1, or 2.3.1. A potential workaround would be to add a custom `Verifier` to the model loading code to ensure that only operators which accept optional inputs use the `-1` special value and only for the tensors that they expect to be optional. Since this allow-list type approach is erro-prone, we advise upgrading to the patched code.SUSE information
Overall state of this security issue: Resolved
This issue is currently rated as having moderate severity.
National Vulnerability Database | |
---|---|
Base Score | 5.8 |
Vector | AV:N/AC:M/Au:N/C:P/I:P/A:N |
Access Vector | Network |
Access Complexity | Medium |
Authentication | None |
Confidentiality Impact | Partial |
Integrity Impact | Partial |
Availability Impact | None |
National Vulnerability Database | |
---|---|
Base Score | 4.8 |
Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N |
Attack Vector | Network |
Attack Complexity | High |
Privileges Required | None |
User Interaction | None |
Scope | Unchanged |
Confidentiality Impact | Low |
Integrity Impact | Low |
Availability Impact | None |
CVSSv3 Version | 3.1 |
SUSE Security Advisories:
- openSUSE-SU-2020:1766-1, published Thu Dec 7 12:55:41 2023
List of released packages
Product(s) | Fixed package version(s) | References |
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openSUSE Leap 15.2 |
| Patchnames: openSUSE-2020-1766 |
SUSE Timeline for this CVE
CVE page created: Sat Sep 26 03:25:04 2020CVE page last modified: Thu Dec 7 13:28:23 2023