# CVE-2019-9803: firefox: The Upgrade-Insecure-Requests (UIR) specification states that if UIR is enabled through Content Security Policy (CSP)...

CVE-2019-9803 is fixed in 4 products on 1 platform, first by firefox 66.0+build3-0ubuntu0.18.04.1, released March 19, 2019. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2019-9803
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0056
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Mar 19, 2019

## Description

The Upgrade-Insecure-Requests (UIR) specification states that if UIR is enabled through Content Security Policy (CSP), navigation to a same-origin URL must be upgraded to HTTPS. Firefox will incorrectly navigate to an HTTP URL rather than perform the security upgrade requested by the CSP in some circumstances, allowing for potential man-in-the-middle attacks on the linked resources. This vulnerability affects Firefox < 66.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | firefox Ubuntu 18.04.6 LTS (bionic) | 66.0+build3-0ubuntu0.18.04.1 | [firefox 66.0+build3-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-66.0-build3-0ubuntu0.18.04.1.md) | Mar 19, 2019 |
| Linux | firefox-globalmenu Ubuntu 18.04.6 LTS (bionic) | 66.0+build3-0ubuntu0.18.04.1 | [firefox-globalmenu 66.0+build3-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-globalmenu-66.0-build3-0ubuntu0.18.04.1.md) | Mar 19, 2019 |
| Linux | firefox-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 66.0+build3-0ubuntu0.18.04.1 | [firefox-mozsymbols 66.0+build3-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-mozsymbols-66.0-build3-0ubuntu0.18.04.1.md) | Mar 19, 2019 |
| Linux | firefox-testsuite Ubuntu 18.04.6 LTS (bionic) | 66.0+build3-0ubuntu0.18.04.1 | [firefox-testsuite 66.0+build3-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-testsuite-66.0-build3-0ubuntu0.18.04.1.md) | Mar 19, 2019 |

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