Name: CVE-2026-103500: Out-of-bounds Write
Creator: Rapid7
Published: 2026-09-30T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-103500, CWE-787, CWE-122, CVSS 6.1, EPSS 0.00277

An attacker could cause a heap buffer overflow by getting a user to open an email that is greater than or equal to 2GB in size. This vulnerability was fixed in Thunderbird 157, Thunderbird 140.17, and Thunderbird 153.4.

CVSS Details

CVSS 3.1 Base Score: 6.1
CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Debian	—	Upgrade thunderbird	Oct 5, 2026	Sep 30, 2026
Mozilla Thunderbird	—	Upgrade to Mozilla Thunderbird version 153.4Upgrade to the latest version of Mozilla Thunderbird	Sep 30, 2026	Sep 30, 2026
Redhat_linux	—	No solution exists	Oct 5, 2026	Sep 30, 2026

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CVSS Details

Covered by Rapid7

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