CVE-2020-26271

Advisory

Tensorflow versions 1.15.5, 2.0.4, 2.1.3, 2.2.2, 2.3.2 and 2.4.0 includes a fix for CVE-2020-26271: In affected versions, under certain cases, loading a saved model can result in accessing uninitialized memory while building the computation graph. The MakeEdge function creates an edge between one output tensor of the src node (given by output_index) and the input slot of the dst node (given by input_index). This is only possible if the types of the tensors on both sides coincide, so the function begins by obtaining the corresponding DataType values and comparing these for equality. However, there is no check that the indices point to inside of the arrays they index into. Thus, this can result in accessing data out of bounds of the corresponding heap allocated arrays. In most scenarios, this can manifest as unitialized data access, but if the index points far away from the boundaries of the arrays this can be used to leak addresses from the library.

Affected package

Affected versions

Fixed versions

Vulnerability changelog

Bug Fixes and Other Changes
* Fixes an access to unitialized memory in Eigen code
([CVE-2020-26266](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-26266))
* Fixes a security vulnerability caused by lack of validation in
`tf.raw_ops.DataFormatVecPermute` and `tf.raw_ops.DataFormatDimMap`
([CVE-2020-26267](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-26267))
* Fixes a vulnerability caused by attempting to write to immutable memory region in
`tf.raw_ops.ImmutableConst`
([CVE-2020-26268](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-26268)
* Fixes a `CHECK`-fail in LSTM with zero-length input
([CVE-2020-26270](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-26270))
* Fixes a security vulnerability caused by accessing heap data outside of bounds
when loading a specially crafted `SavedModel`
([CVE-2020-26271](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-26271))
* Solves an OOM issue on TPUs when XLA contexts use fused average updates
* Updates `libjpeg-turbo` to `2.0.5` to handle
[CVE-2020-13790](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-13790).
* Updates `junit` to `4.13.1` to handle
[CVE-2020-15250](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-15250).
* Updates `PCRE` to `8.44` to handle
[CVE-2019-20838](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-20838)
and
[CVE-2020-14155](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-14155).
* Updates `sqlite3` to `3.44.0` to keep in sync with master branch.

Resources

• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-26271
• https://github.com/tensorflow/tensorflow/commit/0cc38aaa4064fd9e79101994ce9872c6d91f816b
• https://github.com/tensorflow/tensorflow/security/advisories/GHSA-q263-fvxm-m5mw