# CVE-2020-28473: python3-bottle: The package bottle from 0 and before 0.12.19 are vulnerable to Web Cache Poisoning by using a vector called parameter...

CVE-2020-28473 is fixed in 2 products on 1 platform, first by python-bottle 0.12.13-1ubuntu0.1, released January 18, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2020-28473
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0179
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jan 18, 2021

## Description

The package bottle from 0 and before 0.12.19 are vulnerable to Web Cache Poisoning by using a vector called parameter cloaking. When the attacker can separate query parameters using a semicolon (;), they can cause a difference in the interpretation of the request between the proxy (running with default configuration) and the server. This can result in malicious requests being cached as completely safe ones, as the proxy would usually not see the semicolon as a separator, and therefore would not include it in a cache key of an unkeyed parameter.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | python-bottle Ubuntu 18.04.6 LTS (bionic) | 0.12.13-1ubuntu0.1 | [python-bottle 0.12.13-1ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-python-bottle-0.12.13-1ubuntu0.1.md) | Jan 18, 2021 |
| Linux | python3-bottle Ubuntu 18.04.6 LTS (bionic) | 0.12.13-1ubuntu0.1 | [python3-bottle 0.12.13-1ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-python3-bottle-0.12.13-1ubuntu0.1.md) | Jan 18, 2021 |
| Linux | python3-bottle Ubuntu 20.04 LTS (focal) | 0.12.15-2.1ubuntu0.1 | [python3-bottle 0.12.15-2.1ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-python3-bottle-0.12.15-2.1ubuntu0.1.md) | Jan 18, 2021 |

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