CVE-2026-0818 - Vulnerability Details - OpenCVE

CSS-based exfiltration of the content from partially encrypted emails when allowing remote content. This vulnerability affects Thunderbird < 147.0.1 and Thunderbird < 140.7.1.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction Required

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00017.

Exploitation none

Automatable no

Technical Impact partial

No data.

No data.

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://bugzilla.mozilla.org/show_bug.cgi?id=1881530
https://www.mozilla.org/security/advisories/mfsa2026-07/
https://www.mozilla.org/security/advisories/mfsa2026-08/

History

Wed, 28 Jan 2026 17:15:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-116 CWE-200 CWE-352
Metrics		cvssV3_1 `{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N'}` ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Wed, 28 Jan 2026 07:45:00 +0000

Type	Values Removed	Values Added
Description		CSS-based exfiltration of the content from partially encrypted emails when allowing remote content. This vulnerability affects Thunderbird < 147.0.1 and Thunderbird < 140.7.1.
Title		CSS-based exfiltration of the content from partially encrypted emails when allowing remote content
References		https://bugzilla.mozilla.org/show_bug.cgi?id=1881530 https://www.mozilla.org/security/advisories/mfsa2026-07/ https://www.mozilla.org/security/advisories/mfsa2026-08/

Projects

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MITRE

Status: PUBLISHED

Assigner: mozilla

Published: 2026-01-28T07:39:17.467Z

Updated: 2026-01-28T16:51:16.955Z

Reserved: 2026-01-09T16:32:39.712Z

Link: CVE-2026-0818

Vulnrichment

Updated: 2026-01-28T16:49:29.763Z

NVD

Status : Received

Published: 2026-01-28T08:16:03.113

Modified: 2026-01-28T17:16:14.933

Link: CVE-2026-0818

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

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