CVE-2021-29550

critical
Published 2021-05-21 ยท Modified 2023-12-06
CVSS v3
โ€”
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
CVSS v4 NEW
โ€”
not yet in upstream
VIR risk
9.5

Description

TensorFlow is an end-to-end open source platform for machine learning. An attacker can cause a runtime division by zero error and denial of service in `tf.raw_ops.FractionalAvgPool`. This is because the implementation(https://github.com/tensorflow/tensorflow/blob/acc8ee69f5f46f92a3f1f11230f49c6ac266f10c/tensorflow/core/kernels/fractional_avg_pool_op.cc#L85-L89) computes a divisor quantity by dividing two user controlled values. The user controls the values of `input_size[i]` and `pooling_ratio_[i]` (via the `value.shape()` and `pooling_ratio` arguments). If the value in `input_size[i]` is smaller than the `pooling_ratio_[i]`, then the floor operation results in `output_size[i]` being 0. The `DCHECK_GT` line is a no-op outside of debug mode, so in released versions of TF this does not trigger. Later, these computed values are used as arguments(https://github.com/tensorflow/tensorflow/blob/acc8ee69f5f46f92a3f1f11230f49c6ac266f10c/tensorflow/core/kernels/fractional_avg_pool_op.cc#L96-L99) to `GeneratePoolingSequence`(https://github.com/tensorflow/tensorflow/blob/acc8ee69f5f46f92a3f1f11230f49c6ac266f10c/tensorflow/core/kernels/fractional_pool_common.cc#L100-L108). There, the first computation is a division in a modulo operation. Since `output_length` can be 0, this results in runtime crashing. The fix will be included in TensorFlow 2.5.0. We will also cherrypick this commit on TensorFlow 2.4.2, TensorFlow 2.3.3, TensorFlow 2.2.3 and TensorFlow 2.1.4, as these are also affected and still in supported range.

Predictions

Exploit likelihood
20%
Patch ETA
โ€”

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

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OS impact

arch Arch Fixed 1 release
VersionStatusFixed in
โ€” Fixed 2.5.0-1
debian Debian Fixed 2 releases
VersionStatusFixed in
sid Fixed 0
forky Fixed 0

Package impact

EcosystemPackageVulnerableFixed
python PyPItensorflow<2.1.42.1.4
python PyPItensorflow>=2.2.0,<2.2.32.2.3
python PyPItensorflow>=2.3.0,<2.3.32.3.3
python PyPItensorflow>=2.4.0,<2.4.22.4.2
python PyPItensorflow-cpu<2.1.42.1.4
python PyPItensorflow-cpu>=2.2.0,<2.2.32.2.3
python PyPItensorflow-cpu>=2.3.0,<2.3.32.3.3
python PyPItensorflow-cpu>=2.4.0,<2.4.22.4.2
python PyPItensorflow-gpu<2.1.42.1.4
python PyPItensorflow-gpu>=2.2.0,<2.2.32.2.3
python PyPItensorflow-gpu>=2.3.0,<2.3.32.3.3
python PyPItensorflow-gpu>=2.4.0,<2.4.22.4.2
python PyPItensorflow-cpu<548b5eaf23685d86f722233d8fbc21d0a4aecb96||>=2.4.0,<2.4.3548b5eaf23685d86f722233d8fbc21d0a4aecb96
python PyPItensorflow<548b5eaf23685d86f722233d8fbc21d0a4aecb96||>=2.4.0,<2.4.3548b5eaf23685d86f722233d8fbc21d0a4aecb96
python PyPItensorflow-gpu<548b5eaf23685d86f722233d8fbc21d0a4aecb96||>=2.4.0,<2.4.3548b5eaf23685d86f722233d8fbc21d0a4aecb96

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.