# CVE-2020-26270: CHECK-fail in LSTM with zero-length input in TensorFlow > Attackers can cause a denial of service in TensorFlow LSTM/GRU models by providing zero-length inputs, triggering a CHECK failure on CUDA backends. - **Severity:** Medium 4.4 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L`) - **Exploited in the wild:** Not known - **Login needed:** Any signed-in user - **Attackable:** Local or same network only - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 10 Dec 2020 - **Updated:** 4 Aug 2024 - **Also known as:** BIT-tensorflow-2020-26270, GHSA-m648-33qf-v3gp, PYSEC-2020-256, PYSEC-2020-301, PYSEC-2020-336 ## What is CVE-2020-26270? CVE-2020-26270 is a medium-severity denial of service vulnerability in Google Tensorflow, published on 10 Dec 2020. It can only be exploited from the same machine or local network, with no action from the victim. ### Official description In affected versions of TensorFlow running an LSTM/GRU model where the LSTM/GRU layer receives an input with zero-length results in a CHECK failure when using the CUDA backend. This can result in a query-of-death vulnerability, via denial of service, if users can control the input to the layer. This is fixed in versions 1.15.5, 2.0.4, 2.1.3, 2.2.2, 2.3.2, and 2.4.0. Weakness: CWE-20 (Improper Input Validation) ## Which versions are affected by CVE-2020-26270? 34 open source packages ship an affected version, including tensorflow, tensorflow-cpu and tensorflow-gpu. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `tensorflow` | Bitnami | All versions | 1.15.5, 2.0.4, 2.1.3, 2.2.2, 2.3.2 | | `tensorflow` | PyPI | All versions | 1.15.5, 2.0.4, 2.1.3, 2.2.2, 2.3.2 | | `tensorflow` | PyPI | All versions | 1.15.5 | | `tensorflow` | PyPI | All versions | 1.15.5 | | `tensorflow` | PyPI | From 2.0.0 | 2.0.4 | | `tensorflow` | PyPI | From 2.0.0 | 2.0.4 | | `tensorflow` | PyPI | From 2.1.0 | 2.1.3 | | `tensorflow` | PyPI | From 2.1.0 | 2.1.3 | | `tensorflow` | PyPI | From 2.2.0 | 2.2.2 | | `tensorflow` | PyPI | From 2.2.0 | 2.2.2 | | `tensorflow` | PyPI | From 2.3.0 | 2.3.2 | | `tensorflow` | PyPI | From 2.3.0 | 2.3.2 | | `tensorflow-cpu` | PyPI | All versions | 1.15.5, 2.0.4, 2.1.3, 2.2.2, 2.3.2 | | `tensorflow-cpu` | PyPI | All versions | 1.15.5 | | `tensorflow-cpu` | PyPI | All versions | 1.15.5 | | `tensorflow-cpu` | PyPI | From 2.0.0 | 2.0.4 | | `tensorflow-cpu` | PyPI | From 2.0.0 | 2.0.4 | | `tensorflow-cpu` | PyPI | From 2.1.0 | 2.1.3 | | `tensorflow-cpu` | PyPI | From 2.1.0 | 2.1.3 | | `tensorflow-cpu` | PyPI | From 2.2.0 | 2.2.2 | | `tensorflow-cpu` | PyPI | From 2.2.0 | 2.2.2 | | `tensorflow-cpu` | PyPI | From 2.3.0 | 2.3.2 | | `tensorflow-cpu` | PyPI | From 2.3.0 | 2.3.2 | | `tensorflow-gpu` | PyPI | All versions | 1.15.5, 2.0.4, 2.1.3, 2.2.2, 2.3.2 | | `tensorflow-gpu` | PyPI | All versions | 1.15.5 | | `tensorflow-gpu` | PyPI | All versions | 1.15.5 | | `tensorflow-gpu` | PyPI | From 2.0.0 | 2.0.4 | | `tensorflow-gpu` | PyPI | From 2.0.0 | 2.0.4 | | `tensorflow-gpu` | PyPI | From 2.1.0 | 2.1.3 | | `tensorflow-gpu` | PyPI | From 2.1.0 | 2.1.3 | | `tensorflow-gpu` | PyPI | From 2.2.0 | 2.2.2 | | `tensorflow-gpu` | PyPI | From 2.2.0 | 2.2.2 | | `tensorflow-gpu` | PyPI | From 2.3.0 | 2.3.2 | | `tensorflow-gpu` | PyPI | From 2.3.0 | 2.3.2 | Products: Google Tensorflow. ## How do I fix CVE-2020-26270? Upgrade tensorflow to a fixed version for your release line: 1.15.5, 2.0.4, 2.1.3 or 2.2.2. ## Is CVE-2020-26270 being exploited? There is no known exploitation of CVE-2020-26270 in the wild and no public exploit code. ## Other vulnerabilities in Google Tensorflow - [CVE-2023-25668](https://insights.sbomify.com/CVE-2023-25668/): TensorFlow vulnerable to heap out-of-buffer read in the QuantizeAndDequantize operation (critical 9.8) - [CVE-2018-7575](https://insights.sbomify.com/CVE-2018-7575/): Integer Overflow or Wraparound in Google TensorFlow (critical 9.8) - [CVE-2021-37678](https://insights.sbomify.com/CVE-2021-37678/): Arbitrary code execution due to YAML deserialization (critical 9.3) - [CVE-2021-35958](https://insights.sbomify.com/CVE-2021-35958/): Path traversal in n/a (critical 9.1) - [CVE-2020-15202](https://insights.sbomify.com/CVE-2020-15202/): Integer truncation in Shard API usage (critical 9.0) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2020-26270 and fix it if it is affected. What it is: CVE-2020-26270 is a medium-severity denial of service vulnerability in Google Tensorflow, published on 10 Dec 2020. It can only be exploited from the same machine or local network, with no action from the victim. Exploitation: There is no known exploitation of CVE-2020-26270 in the wild and no public exploit code. Affected packages and fixed versions: - tensorflow (Bitnami): affected all versions; fixed in 1.15.5, 2.0.4, 2.1.3, 2.2.2, 2.3.2 - tensorflow (PyPI): affected all versions; fixed in 1.15.5, 2.0.4, 2.1.3, 2.2.2, 2.3.2 - tensorflow (PyPI): affected all versions; fixed in 1.15.5 - tensorflow (PyPI): affected all versions; fixed in 1.15.5 - tensorflow (PyPI): affected from 2.0.0; fixed in 2.0.4 - tensorflow (PyPI): affected from 2.0.0; fixed in 2.0.4 - tensorflow (PyPI): affected from 2.1.0; fixed in 2.1.3 - tensorflow (PyPI): affected from 2.1.0; fixed in 2.1.3 - tensorflow (PyPI): affected from 2.2.0; fixed in 2.2.2 - tensorflow (PyPI): affected from 2.2.0; fixed in 2.2.2 - tensorflow (PyPI): affected from 2.3.0; fixed in 2.3.2 - tensorflow (PyPI): affected from 2.3.0; fixed in 2.3.2 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2020-26270/ (Markdown: https://insights.sbomify.com/CVE-2020-26270/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2020-26270 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-26270 - OSV: https://osv.dev/vulnerability/CVE-2020-26270 --- From sbomify Insights: https://insights.sbomify.com/CVE-2020-26270/ Summaries are generated and may contain mistakes; the official description above is the record.