CVE-2026-84132

HIGH 7.5

Information disclosure in the Networking: HTTP component

CVSS Score

7.5

EPSS Score

0.0%

EPSS Percentile

0th

Information disclosure in the Networking: HTTP component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.

Vendor	mozilla
Product	firefox
Ecosystems	Browser JavaScript
Industries	Technology
Published	Sep 1, 2026
Last Updated	Sep 3, 2026

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Affected Versions

Mozilla / Firefox

All versions affected

Mozilla / Thunderbird

All versions affected

References

NVD ↗ CVE.org ↗ EPSS Data ↗

bugzilla.mozilla.org: https://bugzilla.mozilla.org/show_bug.cgi?id=2063020 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-82/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-85/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-86/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-88/

Credits

Shu Takahashi