CVE-2026-0818
4.3
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Exploitability: 2.8 / Impact: 1.4
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary)
Description
When a user explicitly requested Thunderbird to decrypt an inline OpenPGP message that was embedded in a text section of an email that was formatted and styled with HTML and CSS, then the decrypted contents were rendered in a context in which the CSS styles from the outer messages were active. If the user had additionally allowed loading of the remote content referenced by the outer email message, and the email was crafted by the sender using a combination of CSS rules and fonts and animations, then it was possible to extract the secret contents of the email. This vulnerability was fixed in Thunderbird 147.0.1 and Thunderbird 140.7.1.
Affected (2)
Products: Mozilla: Thunderbird
Configuration A
| Vulnerable Software | Affected Versions |
|---|---|
| Before 147.0.1 |
Related CWEs
CWE-116
Improper Encoding or Escaping of Output
The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.
CWE-200
Exposure of Sensitive Information to an Unauthorized Actor
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
CWE-352
Cross-Site Request Forgery (CSRF)
The web application does not, or can not, sufficiently verify whether a well-formed, valid, consistent request was intentionally provided by the user who submitted the request.
References (4)
Source: security@mozilla.org
Permissions Required
Source: af854a3a-2127-422b-91ae-364da2661108
Timeline
No history available yet.