CVE-2026-0818 (GCVE-0-2026-0818)

Vulnerability from cvelistv5 – Published: 2026-01-28 07:39 – Updated: 2026-01-28 16:51
VLAI?
Title
CSS-based exfiltration of the content from partially encrypted emails when allowing remote content
Summary
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.
Severity ?
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
CWE
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
  • CWE-352 - Cross-Site Request Forgery (CSRF)
  • CWE-116 - Improper Encoding or Escaping of Output
Assigner
References
Impacted products
Vendor Product Version
Mozilla Thunderbird Affected: unspecified , < 147.0.1 (custom)
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    Mozilla Thunderbird Affected: unspecified , < 140.7.1 (custom)
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Credits
Leon Trampert, Daniel Weber, Christian Rossow, Michael Schwarz
Show details on NVD website
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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