CVE-2025-2817: Privilege escalation in Thunderbird Updater

Published Apr 29, 2025
·
Updated

Mozilla Firefox's update mechanism allowed a medium-integrity user process to interfere with the SYSTEM-level updater by manipulating the file-locking behavior. By injecting code into the user-privileged process, an attacker could bypass intended access controls, allowing SYSTEM-level file operations on paths controlled by a non-privileged user and enabling privilege escalation.

Other sources

Thunderbird's update mechanism allowed a medium-integrity user process to interfere with the SYSTEM-level updater by manipulating the file-locking behavior. By injecting code into the user-privileged process, an attacker could bypass intended access controls, allowing SYSTEM-level file operations on paths controlled by a non-privileged user and enabling privilege escalation.

Mozilla

Affected Software

10 affected componentsFixes available
Mozilla Thunderbird<128.10
128.10
Mozilla Firefox ESR<128.10
128.10
Mozilla Firefox<138
138
Mozilla Firefox ESR<115.23
115.23
Mozilla Thunderbird<138
138
Mozilla Firefox<115.23.0
Mozilla Firefox<138.0
Mozilla Firefox>=116.0<128.10.0
Mozilla Thunderbird<128.10.0
Mozilla Thunderbird>=129.0<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-2025-2817?

CVE-2025-2817 is classified as a medium severity vulnerability.

2

How do I fix CVE-2025-2817?

To fix CVE-2025-2817, update your Mozilla Firefox to version 138 or higher, or to Firefox ESR version 115.23 or higher.

3

What products are affected by CVE-2025-2817?

CVE-2025-2817 affects Mozilla Firefox, Firefox ESR, and Thunderbird versions prior to the specified updates.

4

What is the nature of the flaw in CVE-2025-2817?

The flaw in CVE-2025-2817 involves a vulnerable update mechanism that allows a medium-integrity user process to interfere with the SYSTEM-level updater.

5

Can CVE-2025-2817 allow unauthorized file operations?

Yes, CVE-2025-2817 can allow attackers to bypass access controls and perform SYSTEM-level file operations.

Contact

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