by Kastro
Paper/Archive/CVE-2026-16381

CVE-2026-16381

Mozilla Firefox — Same-origin policy bypass in the Networking: DNS component

EPSS 0.2%CVSS 9.1
critical.is priorityof 100
30
CVSS 9.1 (ADP)9.1 / 10 × 3027.3Not in CISA KEV+300.0EPSS percentile 13.9.139 × 202.8No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

Same-origin policy bypass in the Networking: DNS component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

Affected

ProductAffectedFixed inSource
Firefoxsee advisory140.13CNA
Thunderbirdsee advisory140.13CNA

Scores by source

CISA ADP9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refbugzilla.mozilla.org/show_bug.cgi?id=2041001refmozilla.org/security/advisories/mfsa2026-68refmozilla.org/security/advisories/mfsa2026-70refmozilla.org/security/advisories/mfsa2026-71refmozilla.org/security/advisories/mfsa2026-72