CVE-2026-0881: Sandbox escape in the Messaging System component

Published Jan 13, 2026
·
Updated

Sandbox escape in the Messaging System component. This vulnerability affects Firefox < 147.

Other sources

Sandbox escape in the Messaging System component. This vulnerability was fixed in Firefox 147 and Thunderbird 147.

NVD

Affected Software

4 affected componentsFixes available
Mozilla Firefox<147
147
Mozilla Thunderbird<147
147
Mozilla Firefox<147.0
Mozilla Thunderbird<147.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 147
  2. Upgrade

    Upgrade Mozilla Firefox to a version that resolves this vulnerability.

    Fixed in 147
  3. Upgrade

    Upgrade Mozilla Thunderbird to a version that resolves this vulnerability.

    Fixed in 147

Event History

Jan 13, 2026
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
Updated
via Mozilla·12:00 AM
Affected Software
CVE Published
via MITRE·01:30 PM
Data Sourced
via MITRE·01:30 PM
Description
Data Sourced
via Red Hat·02:02 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·02:16 PM
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2026-0881?

CVE-2026-0881 is considered a high-severity vulnerability due to its potential for sandbox escape.

2

How do I fix CVE-2026-0881?

To fix CVE-2026-0881, users should upgrade to Firefox version 147 or later.

3

What versions of Firefox are affected by CVE-2026-0881?

CVE-2026-0881 affects all versions of Firefox prior to version 147.

4

What impact does CVE-2026-0881 have on users?

CVE-2026-0881 allows attackers to escape the browser sandbox, potentially compromising user data and system security.

5

Is there a workaround for CVE-2026-0881?

There are no recommended workarounds for CVE-2026-0881; the best protection is to update to the latest version of Firefox.

Contact

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