CVE-2025-5266: Script element events leaked cross-origin resource status

Published May 27, 2025
·
Updated

Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks.

Affected Software

8 affected componentsFixes available
Mozilla Firefox<139
Mozilla Firefox ESR<128.11
Mozilla Thunderbird<128.11
128.11
Mozilla Thunderbird<139
139
Mozilla Firefox ESR<128.11
128.11
Mozilla Firefox<139
139
Mozilla Firefox<128.11.0
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 Red Hat·01:01 PM
DescriptionSeverityAffected Software
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-2025-5266?

The severity of CVE-2025-5266 is classified as moderate due to its potential to enable XS-Leaks attacks.

2

How do I fix CVE-2025-5266?

To fix CVE-2025-5266, update Mozilla Firefox to version 139 or Firefox ESR to version 128.11.

3

Which versions of Firefox are affected by CVE-2025-5266?

CVE-2025-5266 affects versions of Firefox prior to 139 and Firefox ESR prior to 128.11.

4

What kind of attacks can CVE-2025-5266 enable?

CVE-2025-5266 can enable XS-Leaks attacks by leaking information through load and error events from cross-origin resources.

5

Is user interaction required for CVE-2025-5266 to be exploited?

No, CVE-2025-5266 can be exploited without user interaction, highlighting its significance.

Contact

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