CVE-2025-5271: Devtools' preview ignored CSP headers

Published May 27, 2025
·
Updated

Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks.

Affected Software

4 affected componentsFixes available
Mozilla Firefox<139
Mozilla Thunderbird<139
139
Mozilla Firefox<139
139
Mozilla Firefox<139.0

Event History

May 27, 2025
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·12:29 PM
Data Sourced
via MITRE·12:29 PM
Description
Data Sourced
via NVD·01:15 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-2025-5271?

The severity of CVE-2025-5271 is considered critical due to the potential for content injection attacks.

2

How do I fix CVE-2025-5271?

To fix CVE-2025-5271, update your Firefox browser to version 139 or later.

3

Who is affected by CVE-2025-5271?

CVE-2025-5271 affects all versions of Firefox prior to version 139.

4

What impact does CVE-2025-5271 have?

CVE-2025-5271 could allow attackers to inject malicious content during response previews in Devtools.

5

What does CSP stand for in the context of CVE-2025-5271?

In the context of CVE-2025-5271, CSP stands for Content Security Policy, which is bypassed during response previews.

Contact

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