Exposure of Resource to Wrong Sphere Affecting thunderbird package, versions [,140.14)[141.0,153.1)


Severity

Recommended
0.0
high
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.16% (6th percentile)

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  • Snyk IDSNYK-UNMANAGED-THUNDERBIRD-19427540
  • published29 Aug 2026
  • disclosed18 Aug 2026
  • creditUnknown

Introduced: 18 Aug 2026

NewCVE-2026-74934  (opens in a new tab)
CWE-668  (opens in a new tab)

How to fix?

Upgrade thunderbird to version 140.14, 153.1 or higher.

Overview

Affected versions of this package are vulnerable to Exposure of Resource to Wrong Sphere in the CanvasWebGL component of the graphics subsystem. An attacker can bypass site isolation protections by exploiting improper separation of web content, potentially allowing unauthorized access to data from other sites.

CVSS Base Scores

version 4.0
version 3.1