CVE-2026-2778
Received Received - Intake
Sandbox Escape via DOM Boundary Error in Firefox

Publication date: 2026-02-24

Last updated on: 2026-04-13

Assigner: Mozilla Corporation

Description
Sandbox escape due to incorrect boundary conditions in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.
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Meta Information
Published
2026-02-24
Last Modified
2026-04-13
Generated
2026-06-16
AI Q&A
2026-02-24
EPSS Evaluated
2026-06-15
NVD
CVE-2026-2778
Affected Vendors & Products
Showing 5 associated CPEs
Vendor Product Version / Range
mozilla firefox to 148.0 (exc)
mozilla thunderbird to 148.0 (exc)
mozilla firefox to 115.33.0 (exc)
mozilla firefox From 128.0 (inc) to 140.8.0 (exc)
mozilla thunderbird to 140.8.0 (exc)
Helpful Resources
Exploitability
CWE
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KEV
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CWE ID Description
CWE-119 The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
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Executive Summary

This vulnerability is a sandbox escape caused by incorrect boundary conditions in the DOM: Core & HTML component of Firefox. It affects versions of Firefox earlier than 148, Firefox ESR earlier than 115.33, and Firefox ESR earlier than 140.8.

Impact Analysis

The vulnerability allows an attacker to escape the sandbox environment, potentially enabling them to execute code or access resources outside the intended restricted environment, which can lead to unauthorized actions or compromise of the system running the affected Firefox versions.

Compliance Impact

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