Firefox WebRender Privilege Escalation before 152
CVE-2026-12289 Published on June 16, 2026

Privilege escalation in the Graphics: WebRender component
Privilege escalation in the Graphics: WebRender component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.

NVD

Vulnerability Analysis

CVE-2026-12289 can be exploited with network access, requires user interaction. This vulnerability is consided to have a high level of attack complexity. The potential impact of an exploit of this vulnerability is considered to be very high.

Attack Vector:

NETWORK

Attack Complexity:

HIGH

Privileges Required:

NONE

User Interaction:

REQUIRED

Scope:

UNCHANGED

Confidentiality Impact:

HIGH

Integrity Impact:

HIGH

Availability Impact:

HIGH

Weakness Types

Improper Privilege Management

The software does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.

Incorrect Privilege Assignment

A product incorrectly assigns a privilege to a particular actor, creating an unintended sphere of control for that actor.

Products Associated with CVE-2026-12289

You can be notified by email with stack.watch whenever vulnerabilities like CVE-2026-12289 are published in these products:

Mozilla Firefox

Mozilla Thunderbird

Red Hat Enterprise Linux (RHEL)

Red Hat Enterprise Linux Eus

Red Hat Rhel Aus

Red Hat Rhel Eus Long Life

Red Hat Rhel E4s

Red Hat Rhel Tus

Red Hat Rhel Eus

Red Hat Rhel Els

Affected Versions

Mozilla Firefox:

Version 115.37, <= 115.* is unaffected.
Version 140.12, <= 140.* is unaffected.
Version 152, <= * is unaffected.

Mozilla Thunderbird:

Version 140.12, <= 140.* is unaffected.
Version 152, <= * is unaffected.

Red Hat Enterprise Linux 10:

Version 0:140.12.0-1.el10_2 and below * is unaffected.

Red Hat Enterprise Linux 10:

Version 0:140.12.0-1.el10_2 and below * is unaffected.

Red Hat Enterprise Linux 10.0 Extended Update Support:

Version 0:140.12.0-1.el10_0 and below * is unaffected.

Red Hat Enterprise Linux 10.0 Extended Update Support:

Version 0:140.12.0-1.el10_0 and below * is unaffected.

Red Hat Enterprise Linux 7 Extended Lifecycle Support:

Version 0:140.12.0-1.el7_9 and below * is unaffected.

Red Hat Enterprise Linux 8:

Version 0:140.12.0-1.el8_10 and below * is unaffected.

Red Hat Enterprise Linux 8:

Version 0:140.12.0-1.el8_10 and below * is unaffected.

Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support:

Version 0:140.12.0-1.el8_4 and below * is unaffected.

Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support:

Version 0:140.12.0-1.el8_4 and below * is unaffected.

Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On:

Version 0:140.12.0-1.el8_4 and below * is unaffected.

Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On:

Version 0:140.12.0-1.el8_4 and below * is unaffected.

Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support:

Version 0:140.12.0-1.el8_6 and below * is unaffected.

Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support:

Version 0:140.12.0-1.el8_6 and below * is unaffected.

Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On:

Version 0:140.12.0-1.el8_6 and below * is unaffected.

Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On:

Version 0:140.12.0-1.el8_6 and below * is unaffected.

Red Hat Enterprise Linux 8.8 Telecommunications Update Service:

Version 0:140.12.0-1.el8_8 and below * is unaffected.

Red Hat Enterprise Linux 8.8 Telecommunications Update Service:

Version 0:140.12.0-1.el8_8 and below * is unaffected.

Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions:

Version 0:140.12.0-1.el8_8 and below * is unaffected.

Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions:

Version 0:140.12.0-1.el8_8 and below * is unaffected.

Red Hat Enterprise Linux 9:

Version 0:140.12.0-1.el9_8 and below * is unaffected.

Red Hat Enterprise Linux 9:

Version 0:140.12.0-1.el9_8 and below * is unaffected.

Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions:

Version 0:140.12.0-1.el9_2 and below * is unaffected.

Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions:

Version 0:140.12.0-1.el9_4 and below * is unaffected.

Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions:

Version 0:140.12.0-1.el9_4 and below * is unaffected.

Red Hat Enterprise Linux 9.6 Extended Update Support:

Version 0:140.12.0-1.el9_6 and below * is unaffected.

Red Hat Enterprise Linux 9.6 Extended Update Support:

Version 0:140.12.0-1.el9_6 and below * is unaffected.

Red Hat Enterprise Linux 10: Red Hat Enterprise Linux 10: Red Hat Enterprise Linux 6: Red Hat Enterprise Linux 6: Red Hat Enterprise Linux 7:

Exploit Probability

EPSS

0.32%

Percentile

23.08%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.

Firefox WebRender Privilege Escalation before 152CVE-2026-12289 Published on June 16, 2026

Vulnerability Analysis

Weakness Types

Improper Privilege Management

Incorrect Privilege Assignment

Products Associated with CVE-2026-12289

Affected Versions

Exploit Probability

Firefox WebRender Privilege Escalation before 152
CVE-2026-12289 Published on June 16, 2026