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.
CVSS Details
- CVSS 3.1 Base Score: 7.4
- CVSS 3.0 Vector: (CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Arch Linux | — | Upgrade to the latest version of Arch Linux | Jul 11, 2025 | Apr 26, 2019 |
| Freebsd | — | Upgrade libxulUpgrade firefoxUpgrade seamonkeyUpgrade linux-firefoxUpgrade waterfoxUpgrade linux-seamonkeyUpgrade thunderbirdUpgrade firefox-esrUpgrade linux-thunderbird | Mar 20, 2019 | Mar 19, 2019 |
| Mfsa2019 07 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox version 66.0 | Mar 20, 2019 | Mar 19, 2019 |
| Ubuntu | — | Upgrade firefox | Apr 1, 2019 | Mar 19, 2019 |
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