Name: CVE-2026-74989: Improper Restriction of Operations within the Bounds of a Memory Buffer
Creator: Rapid7
Published: 2026-08-18T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-74989, CWE-119, CVSS 9.8, EPSS 0.0057

Internally found bugs present in Firefox 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154 and Thunderbird 154.

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
Mfsa2026 74	—	Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox version 154.0	Aug 18, 2026	Aug 18, 2026
Mozilla Thunderbird	—	Upgrade to the latest version of Mozilla ThunderbirdUpgrade to Mozilla Thunderbird version 154.0	Aug 18, 2026	Aug 18, 2026

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CVSS Details

Covered by Rapid7

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