# CVE-2018-20406: Python 3.6 and 2 others: Modules/_pickle.c in Python before 3.7.1 has an integer overflow via a large LONG_BINPUT value that is…

CVE-2018-20406 is fixed in 10 products on 2 platforms, first by Python 3.7 3.7.1, released October 20, 2018. 2 other affected products have no fix yet. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2018-20406
- Priority: High
- CVSS: 7.5 (Low)
- EPSS: 0.0579
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Dec 22, 2018
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2018-20406

## Description

Modules/_pickle.c in Python before 3.7.1 has an integer overflow via a large LONG_BINPUT value that is mishandled during a "resize to twice the size" attempt. This issue might cause memory exhaustion, but is only relevant if the pickle format is used for serializing tens or hundreds of gigabytes of data. This issue is fixed in: v3.4.10, v3.4.10rc1; v3.5.10, v3.5.10rc1, v3.5.7, v3.5.7rc1, v3.5.8, v3.5.8rc1, v3.5.8rc2, v3.5.9; v3.6.10, v3.6.10rc1, v3.6.11, v3.6.11rc1, v3.6.12, v3.6.7, v3.6.7rc1, v3.6.7rc2, v3.6.8, v3.6.8rc1, v3.6.9, v3.6.9rc1; v3.7.1, v3.7.1rc1, v3.7.1rc2, v3.7.2, v3.7.2rc1, v3.7.3, v3.7.3rc1, v3.7.4, v3.7.4rc1, v3.7.4rc2, v3.7.5, v3.7.5rc1, v3.7.6, v3.7.6rc1, v3.7.7, v3.7.7rc1, v3.7.8, v3.7.8rc1, v3.7.9.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Python 3.7 | 3.7.1 | [Python 3.7 3.7.1](https://patchblox.com/security/data/fix/windows-app/python.python.3.7-3.7.1.md) | Oct 20, 2018 |
| Linux | idle-python3.6 Ubuntu 18.04.6 LTS (bionic) | 3.6.7-1~18.04 | [idle-python3.6 3.6.7-1~18.04](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-idle-python3.6-3.6.7-1-18.04.md) | Dec 22, 2018 |
| Linux | libpython3.6 Ubuntu 18.04.6 LTS (bionic) | 3.6.7-1~18.04 | [libpython3.6 3.6.7-1~18.04](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libpython3.6-3.6.7-1-18.04.md) | Dec 22, 2018 |
| Linux | libpython3.6-minimal Ubuntu 18.04.6 LTS (bionic) | 3.6.7-1~18.04 | [libpython3.6-minimal 3.6.7-1~18.04](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libpython3.6-minimal-3.6.7-1-18.04.md) | Dec 22, 2018 |
| Linux | libpython3.6-stdlib Ubuntu 18.04.6 LTS (bionic) | 3.6.7-1~18.04 | [libpython3.6-stdlib 3.6.7-1~18.04](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libpython3.6-stdlib-3.6.7-1-18.04.md) | Dec 22, 2018 |
| Linux | libpython3.6-testsuite Ubuntu 18.04.6 LTS (bionic) | 3.6.7-1~18.04 | [libpython3.6-testsuite 3.6.7-1~18.04](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libpython3.6-testsuite-3.6.7-1-18.04.md) | Dec 22, 2018 |
| Linux | python3.6 Ubuntu 18.04.6 LTS (bionic) | 3.6.7-1~18.04 | [python3.6 3.6.7-1~18.04](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-python3.6-3.6.7-1-18.04.md) | Dec 22, 2018 |
| Linux | python3.6-examples Ubuntu 18.04.6 LTS (bionic) | 3.6.7-1~18.04 | [python3.6-examples 3.6.7-1~18.04](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-python3.6-examples-3.6.7-1-18.04.md) | Dec 22, 2018 |
| Linux | python3.6-minimal Ubuntu 18.04.6 LTS (bionic) | 3.6.7-1~18.04 | [python3.6-minimal 3.6.7-1~18.04](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-python3.6-minimal-3.6.7-1-18.04.md) | Dec 22, 2018 |
| Linux | python3.6-venv Ubuntu 18.04.6 LTS (bionic) | 3.6.7-1~18.04 | [python3.6-venv 3.6.7-1~18.04](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-python3.6-venv-3.6.7-1-18.04.md) | Dec 22, 2018 |

## No fix yet

| Platform | Product | Status |
|---|---|---|
| Windows apps | Python 3.5 | no-fix |
| Windows apps | Python 3.6 | no-fix |

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