# CVE-2018-1000656: python3-flask: The Pallets Project flask version Before 0.12.3 contains a CWE-20: Improper Input Validation vulnerability in flask t...

CVE-2018-1000656 is fixed in 2 products on 1 platform, first by python-flask 0.12.2-3ubuntu0.1, released August 20, 2018. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2018-1000656
- Priority: Routine
- CVSS: n/a (Low)
- EPSS: 0.0386
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 20, 2018

## Description

The Pallets Project flask version Before 0.12.3 contains a CWE-20: Improper Input Validation vulnerability in flask that can result in Large amount of memory usage possibly leading to denial of service. This attack appear to be exploitable via Attacker provides JSON data in incorrect encoding. This vulnerability appears to have been fixed in 0.12.3. NOTE: this may overlap CVE-2019-1010083.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | python-flask Ubuntu 18.04.6 LTS (bionic) | 0.12.2-3ubuntu0.1 | [python-flask 0.12.2-3ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-python-flask-0.12.2-3ubuntu0.1.md) | Aug 20, 2018 |
| Linux | python3-flask Ubuntu 18.04.6 LTS (bionic) | 0.12.2-3ubuntu0.1 | [python3-flask 0.12.2-3ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-python3-flask-0.12.2-3ubuntu0.1.md) | Aug 20, 2018 |

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Data as of 2026-11-07T18:46:35Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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