Description
Denial-of-service in the PDF Viewer component. This vulnerability was fixed in Firefox 155 and Thunderbird 155.
Affected products
mozilla: firefox; mozilla: thunderbird
References3
- www.mozilla.org/security/advisories/mfsa2026-82/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-86/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=2056164 Issue Tracking
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 31 · as of 8 November 2026
- CWE
- CWE-400
Could this be exploited in your environment?
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