Setting a nameless cookie with an equals sign in the value shadowed other cookies. Even if the nameless cookie was set over HTTP and the shadowed cookie included the `Secure` attribute. This vulnerability was fixed in Firefox 141, Firefox ESR 140.1, Thunderbird 141, and Thunderbird 140.1.
CVSS Details
- CVSS 3.1 Base Score: 9.1
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Freebsd | — | Upgrade thunderbirdUpgrade firefoxUpgrade firefox-esrUpgrade thunderbird-esr | Jul 25, 2025 | Jul 24, 2025 |
| Mfsa2025 56 | — | Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox version 141.0 | Jul 23, 2025 | Jul 22, 2025 |
| Mfsa2025 59 | — | Upgrade to Mozilla Firefox ESR version 140.1Upgrade to the latest version of Mozilla Firefox | Jul 23, 2025 | Jul 22, 2025 |
| Mozilla Thunderbird | — | Upgrade to Mozilla Thunderbird version 140.1Upgrade to the latest version of Mozilla Thunderbird | Jul 23, 2025 | Jul 22, 2025 |
| Suse | — | Upgrade mozillafirefox-branding-sleUpgrade pipewire-modulesUpgrade libpipewire-0_3-0Upgrade MozillaFirefoxUpgrade mozillafirefox-branding-upstreamUpgrade MozillaThunderbird-translations-commonUpgrade pipewire-langUpgrade xdg-desktop-portalUpgrade MozillaFirefox-translations-commonUpgrade pipewire-spa-plugins-0_2Upgrade xdg-desktop-portal-langUpgrade xdg-desktop-portal-develUpgrade gstreamer-plugin-pipewireUpgrade pipewireUpgrade pipewire-spa-toolsUpgrade MozillaFirefox-develUpgrade pipewire-toolsUpgrade MozillaThunderbird-translations-otherUpgrade MozillaFirefox-translations-otherUpgrade pipewire-modules-0_3Upgrade MozillaThunderbird | Dec 5, 2025 | Jul 25, 2025 |
| Ubuntu | — | Upgrade thunderbird | Jul 24, 2025 | Jul 22, 2025 |
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