CVE-2025-8034: Memory safety bugs fixed in Firefox ESR 115.26, Firefox ESR 128.13, Thunderbird ESR 128.13, Firefox ESR 140.1, Thunderbird ESR 140.1, Firefox 141 and Thunderbird 141

Published Jul 22, 2025
·
Updated

Memory safety bugs present in Firefox ESR 115.25, Firefox ESR 128.12, Thunderbird ESR 128.12, Firefox ESR 140.0, Thunderbird ESR 140.0, Firefox 140 and Thunderbird 140. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.

Affected Software

14 affected componentsFixes available
Mozilla Firefox ESR<115.26
115.26
Mozilla Firefox<141
141
Mozilla Firefox ESR<128.13
128.13
Mozilla Firefox ESR<140.1
140.1
Mozilla Thunderbird<128.13
128.13
Mozilla Thunderbird<141
141
Mozilla Thunderbird<140.1
140.1
Mozilla Firefox<115.26.0
Mozilla Firefox<141.0
Mozilla Firefox>=128.0<128.13.0
Mozilla Firefox>=140.0<140.1.0
Mozilla Thunderbird<128.13.0
Mozilla Thunderbird<141.0
Mozilla Thunderbird>=140.0<140.1.0

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 140.1
  2. Upgrade

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

    Fixed in 128.13
  3. Upgrade

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

    Fixed in 141
  4. Upgrade

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

    Fixed in 115.26
  5. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 141
  6. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 115.26
  7. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 128.13
  8. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 140.1
  9. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 141
  10. Upgrade

    Upgrade Thunderbird ESR to a version that resolves this vulnerability.

    Fixed in 128.13
  11. Upgrade

    Upgrade Thunderbird ESR to a version that resolves this vulnerability.

    Fixed in 140.1

Event History

Jul 22, 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·08:49 PM
Data Sourced
via MITRE·08:49 PM
Description
Data Sourced
via Red Hat·09:02 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·09:15 PM
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2025-8034?

CVE-2025-8034 is classified as a critical vulnerability due to the potential for memory corruption exploitation.

2

How do I fix CVE-2025-8034?

To mitigate CVE-2025-8034, update your affected software to the latest versions: Firefox ESR 115.26, 128.13, 140.1, or Firefox 141.

3

Which software versions are affected by CVE-2025-8034?

CVE-2025-8034 affects Firefox ESR versions 115.25, 128.12, 140.0, Thunderbird ESR versions 128.12, 140.0, and Firefox version 140.

4

What types of issues are associated with CVE-2025-8034?

CVE-2025-8034 involves memory safety bugs that may lead to memory corruption.

5

Is user data at risk due to CVE-2025-8034?

Yes, because of its memory corruption nature, CVE-2025-8034 could potentially lead to unauthorized access to user data.

Contact

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