Name: CVE-2026-100794: Improper Restriction of Operations within the Bounds of a Memory Buffer
Creator: Rapid7
Published: 2026-09-29T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-100794, CWE-119, CVSS 9.6, EPSS 0.00156

Sandbox escape due to incorrect boundary conditions in the Internationalization component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.

CVSS Details

CVSS 3.1 Base Score: 9.6
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Amazon Linux Ami 2	—	Upgrade firefox	Oct 19, 2026	Oct 19, 2026
Amazon_linux_2023	—	Upgrade firefoxUpgrade firefox-debugsourceUpgrade firefox-debuginfo	Oct 13, 2026	Sep 29, 2026
Debian	—	Upgrade firefox-esrUpgrade thunderbird	Oct 1, 2026	Sep 29, 2026
Mfsa2026 100	—	Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox ESR version 153.4	Sep 29, 2026	Sep 29, 2026
Mfsa2026 97	—	Upgrade to Mozilla Firefox version 157.0Upgrade to the latest version of Mozilla Firefox	Sep 29, 2026	Sep 29, 2026
Mfsa2026 99	—	Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox ESR version 140.17	Sep 29, 2026	Sep 29, 2026
Mozilla Thunderbird	—	Upgrade to the latest version of Mozilla ThunderbirdUpgrade to Mozilla Thunderbird version 153.4	Sep 30, 2026	Sep 30, 2026
Oracle_linux	—	Upgrade firefox-x11Upgrade thunderbirdUpgrade firefox	Oct 22, 2026	Sep 29, 2026
Redhat_linux	—	No solution exists	Oct 19, 2026	Sep 29, 2026

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CVSS Details

Covered by Rapid7

Prioritize with Active Threat Intelligence