CVE-2021-29542
Heap buffer overflow in `StringNGrams`
Description
TensorFlow is an end-to-end open source platform for machine learning. An attacker can cause a heap buffer overflow by passing crafted inputs to `tf.raw_ops.StringNGrams`. This is because the implementation(https://github.com/tensorflow/tensorflow/blob/1cdd4da14282210cc759e468d9781741ac7d01bf/tensorflow/core/kernels/string_ngrams_op.cc#L171-L185) fails to consider corner cases where input would be split in such a way that the generated tokens should only contain padding elements. If input is such that `num_tokens` is 0, then, for `data_start_index=0` (when left padding is present), the marked line would result in reading `data[-1]`. 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.
How to fix CVE-2021-29542
To remediate CVE-2021-29542, upgrade the affected package to a fixed version below.
- —upgrade to 2.1.4 or later
- —upgrade to 2.1.4 or later
- —upgrade to ba424dd8f16f7110eea526a8086f1a155f14f22b or later
- —upgrade to ba424dd8f16f7110eea526a8086f1a155f14f22b or later
- —upgrade to 2.1.4 or later
- —upgrade to ba424dd8f16f7110eea526a8086f1a155f14f22b or later
- —upgrade to 2.1.4 or later
Is CVE-2021-29542 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (7)
- from 0, < 2.1.4, >= 2.2.0, < 2.2.3, >= 2.3.0, < 2.3.3, >= 2.4.0, < 2.4.2
- from 0, < 2.1.4
- from 0, < ba424dd8f16f7110eea526a8086f1a155f14f22b | from 0, < 2.1.4, >= 2.2.0, < 2.2.3, >= 2.3.0, < 2.3.3, >= 2.4.0, < 2.4.2
- from 0, < ba424dd8f16f7110eea526a8086f1a155f14f22b | from 0, < 2.1.4, >= 2.2.0, < 2.2.3, >= 2.3.0, < 2.3.3, >= 2.4.0, < 2.4.2
- from 0, < 2.1.4
- from 0, < ba424dd8f16f7110eea526a8086f1a155f14f22b | from 0, < 2.1.4, >= 2.2.0, < 2.2.3, >= 2.3.0, < 2.3.3, >= 2.4.0, < 2.4.2
- from 0, < 2.1.4
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N |
| osv | CVSS 3.1 | LOW2.5 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L |