CVE-2026-100821

MEDIUM 4.7CVE-2026-100821 · Published 29/09/2026 · updated 13/10/2026

Package	Affected versions	Patched versions
firefox mozilla	`≥ 116.0.0, < 140.17.0≥ 141.0.0, < 153.4.0≥ 154.0.0, < 157.0.0< 115.42.0`	`140.17.0153.4.0157.0.0115.42.0`
thunderbird mozilla	`≥ 141.0, < 153.4.0≥ 154.0, < 157.0< 140.17.0`	`153.4.0157.0140.17.0`

Description

Site isolation issue in the Panning and Zooming component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.

References

bugzilla.mozilla.org/show_bug.cgi · Permissions Required
mozilla.org/security/advisories/mfsa2026-100 · Vendor Advisory
mozilla.org/security/advisories/mfsa2026-101 · Vendor Advisory
mozilla.org/security/advisories/mfsa2026-102 · Vendor Advisory
mozilla.org/security/advisories/mfsa2026-103 · Vendor Advisory
mozilla.org/security/advisories/mfsa2026-97 · Vendor Advisory
mozilla.org/security/advisories/mfsa2026-98 · Vendor Advisory
mozilla.org/security/advisories/mfsa2026-99 · Vendor Advisory

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