Name: CVE-2026-4729: Buffer Copy without Checking Size of Input
Creator: Rapid7
Published: 2026-03-24T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-4729, CWE-825, CWE-120, CVSS 9.8, EPSS 0.0033

Memory safety bugs present in Firefox 148 and Thunderbird 148. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 149 and Thunderbird 149.

CVSS Details

CVSS 3.1 Base Score: 9.8
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Freebsd	—	Upgrade thunderbirdUpgrade firefox	Mar 27, 2026	Mar 26, 2026
Mfsa2026 20	—	Upgrade to Mozilla Firefox version 149.0Upgrade to the latest version of Mozilla Firefox	Mar 27, 2026	Mar 24, 2026
Mozilla Thunderbird	—	Upgrade to Mozilla Thunderbird version 149.0Upgrade to the latest version of Mozilla Thunderbird	Mar 27, 2026	Mar 24, 2026

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CVSS Details

Covered by Rapid7

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