If a server sends two Strict-Transport-Security (STS) headers for a single connection, they will be rejected as invalid and HTTP Strict Transport Security (HSTS) will not be enabled for the connection. This vulnerability affects Firefox < 55.
CVSS Details
- CVSS 3.1 Base Score: 5.3
- CVSS 3.0 Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/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 | Jun 11, 2018 |
| Freebsd | — | Upgrade firefox-esrUpgrade firefoxUpgrade linux-thunderbirdUpgrade thunderbirdUpgrade seamonkeyUpgrade linux-seamonkeyUpgrade linux-firefoxUpgrade libxul | Aug 8, 2017 | Aug 8, 2017 |
| Mfsa2017 18 | — | Upgrade to Mozilla Firefox version 55.0Upgrade to the latest version of Mozilla Firefox | Aug 9, 2017 | Aug 8, 2017 |
| Suse | — | Upgrade MozillaFirefoxUpgrade MozillaFirefox-translations-commonUpgrade MozillaFirefox-translations-otherUpgrade MozillaFirefox-devel | May 20, 2018 | Aug 8, 2017 |
| Ubuntu | — | Upgrade firefox | Aug 16, 2017 | Aug 8, 2017 |
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