// For flags

CVE-2025-2817

firefox: thunderbird: Privilege escalation in Firefox Updater

Severity Score

8.8
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track*
*SSVC
Descriptions

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. This vulnerability affects Firefox < 138, Firefox ESR < 128.10, Firefox ESR < 115.23, Thunderbird < 138, and Thunderbird ESR < 128.10.

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. This vulnerability affects Firefox < 138, Firefox ESR < 128.10, Firefox ESR < 115.23, Thunderbird < 138, and Thunderbird < 128.10.

A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue: 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.

An update for firefox is now available for Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions. Issues addressed include bypass and privilege escalation vulnerabilities.

*Credits: Dong-uk Kim (@justlikebono)
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Attack Vector
Network
Attack Complexity
High
Privileges Required
Low
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High
Attack Vector
Network
Attack Complexity
Low
Authentication
Single
Confidentiality
Complete
Integrity
Complete
Availability
Complete
* Common Vulnerability Scoring System
SSVC
  • Decision:Track*
Exploitation
None
Automatable
No
Tech. Impact
Total
* Organization's Worst-case Scenario
Timeline
  • 2025-03-26 CVE Reserved
  • 2025-04-29 CVE Published
  • 2025-05-01 CVE Updated
  • 2025-05-05 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
  • CWE-94: Improper Control of Generation of Code ('Code Injection')
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Mozilla
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 Firefox
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*-
Affected
Mozilla
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 Firefox Esr
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*-
Affected
Mozilla
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 Thunderbird
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*-
Affected
Fedoraproject
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 Fedora
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*-
Affected
Slackware
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 Slackware Linux
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*-
Affected
Suse
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 Sles-ltss-extended-security
Search vendor "Suse" for product "Sles-ltss-extended-security"
*-
Affected
Suse
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 Sles-ltss
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*-
Affected