# CVE-2017-7821: firefox: A vulnerability where WebExtensions can download and attempt to open a file of some non-executable file types

CVE-2017-7821 is fixed in 4 products on 1 platform, first by firefox 56.0+build6-0ubuntu1, released October 1, 2017. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2017-7821
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0191
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 1, 2017

## Description

A vulnerability where WebExtensions can download and attempt to open a file of some non-executable file types. This can be triggered without specific user interaction for the file download and open actions. This could be used to trigger known vulnerabilities in the programs that handle those document types. This vulnerability affects Firefox < 56.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | firefox Ubuntu 18.04.6 LTS (bionic) | 56.0+build6-0ubuntu1 | [firefox 56.0+build6-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-56.0-build6-0ubuntu1.md) | Oct 1, 2017 |
| Linux | firefox-globalmenu Ubuntu 18.04.6 LTS (bionic) | 56.0+build6-0ubuntu1 | [firefox-globalmenu 56.0+build6-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-globalmenu-56.0-build6-0ubuntu1.md) | Oct 1, 2017 |
| Linux | firefox-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 56.0+build6-0ubuntu1 | [firefox-mozsymbols 56.0+build6-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-mozsymbols-56.0-build6-0ubuntu1.md) | Oct 1, 2017 |
| Linux | firefox-testsuite Ubuntu 18.04.6 LTS (bionic) | 56.0+build6-0ubuntu1 | [firefox-testsuite 56.0+build6-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-testsuite-56.0-build6-0ubuntu1.md) | Oct 1, 2017 |

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