CVE-2025-4087: Unsafe attribute access during XPath parsing

Published Apr 29, 2025
·
Updated

A vulnerability was identified in Firefox where XPath parsing could trigger undefined behavior due to missing null checks during attribute access. This could lead to out-of-bounds read access and potentially, memory corruption.

Other sources

A vulnerability was identified in Thunderbird where XPath parsing could trigger undefined behavior due to missing null checks during attribute access. This could lead to out-of-bounds read access and potentially, memory corruption.

Mozilla

Affected Software

12 affected componentsFixes available
Mozilla Firefox<138
Mozilla Firefox ESR<128.10
Mozilla Thunderbird<138
Mozilla Thunderbird<128.10
Mozilla Thunderbird<128.10
128.10
Mozilla Firefox<138
138
Mozilla Thunderbird<138
138
Mozilla Firefox ESR<128.10
128.10
Mozilla Firefox<128.10
Mozilla Firefox<138.0
Mozilla Thunderbird<128.10.0
Mozilla Thunderbird<138.0

Event History

Apr 29, 2025
CVE Published
via Mozilla·12:00 AM
CVE Published
via MITRE·01:13 PM
Data Sourced
via MITRE·01:13 PM
Description
Data Sourced
via Red Hat·02:01 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·02:15 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-2025-4087?

CVE-2025-4087 has a high severity as it can lead to out-of-bounds read access and potential memory corruption.

2

How do I fix CVE-2025-4087?

To fix CVE-2025-4087, update to Firefox version 138 or later, Firefox ESR version 128.10 or later, or the appropriate version for Thunderbird.

3

What software is affected by CVE-2025-4087?

CVE-2025-4087 affects Firefox versions prior to 138, Firefox ESR versions prior to 128.10, and Thunderbird versions prior to 138.

4

What kind of attacks can CVE-2025-4087 facilitate?

CVE-2025-4087 can facilitate attacks that exploit memory corruption vulnerabilities, potentially leading to system crashes or arbitrary code execution.

5

Is CVE-2025-4087 specific to desktop versions of the software?

CVE-2025-4087 affects desktop versions of Firefox and Thunderbird, including their ESR counterparts.

Contact

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