CVE-2026-0887
firefox: thunderbird: Clickjacking issue, information disclosure in the PDF Viewer component
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · January 13, 2026
Updated · October 16, 2026
Description
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue: Clickjacking issue, information disclosure in the PDF Viewer component
Statement
Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. Updating to a version that contains the upstream fix (Firefox 147 or Firefox ESR 140.7, and Thunderbird 147 or Thunderbird 140.7, or later) addresses this issue.
CVSS / CWE
CVSS 3.1 · 6.1CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CWE-497 · Exposure of Sensitive System Information to an Unauthorized Control Sphere