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vulnerability

Red Hat: CVE-2022-29916: CVE-2022-29916 Mozilla: Leaking browser history with CSS variables (Multiple Advisories)

Severity
8
CVSS
(AV:N/AC:H/Au:N/C:C/I:C/A:C)
Published
May 4, 2022
Added
May 5, 2022
Modified
Mar 27, 2026

Description

Firefox behaved slightly differently for already known resources when loading CSS resources involving CSS variables. This could have been used to probe the browser history. This vulnerability affects Thunderbird < 91.9, Firefox ESR < 91.9, and Firefox < 100.

Solutions

redhat-upgrade-firefoxredhat-upgrade-firefox-debuginforedhat-upgrade-firefox-debugsourceredhat-upgrade-thunderbirdredhat-upgrade-thunderbird-debuginforedhat-upgrade-thunderbird-debugsource

References

    Title
    Rapid7 Labs

    2026 Global Threat Landscape Report

    The predictive window has collapsed. Exploitation follows disclosure in days. See how attackers are accelerating and how to stay ahead.