Out-of-bounds Read in Google Tensorflow

CVE-2020-26271

In affected versions of TensorFlow 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. This is fixed in versions 1.15.5, 2.0.4, 2.1.3, 2.2.2, 2.3.2, and 2.4.0.

Vulnerability class: Buffer Overflow

EPSS: 0.002 (11.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-26271?
CVE-2020-26271 is a medium-severity vulnerability in Google Tensorflow, classified under Out-of-bounds Read. CVSS score: 4.4/10. Published 2020-12-10.
How severe is CVE-2020-26271?
Medium severity. CVSS v3 base score is 4.4 out of 10.