CVE-2025-5986 (GCVE-0-2025-5986)
Vulnerability from cvelistv5
Published
2025-06-11 12:07
Modified
2025-06-11 13:20
Severity ?
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CWE
  • Unsolicited File Download, Disk Space Exhaustion, and Credential Leakage via mailbox:/// Links
Summary
A crafted HTML email using mailbox:/// links can trigger automatic, unsolicited downloads of .pdf files to the user's desktop or home directory without prompting, even if auto-saving is disabled. This behavior can be abused to fill the disk with garbage data (e.g. using /dev/urandom on Linux) or to leak Windows credentials via SMB links when the email is viewed in HTML mode. While user interaction is required to download the .pdf file, visual obfuscation can conceal the download trigger. Viewing the email in HTML mode is enough to load external content. This vulnerability affects Thunderbird < 128.11.1 and Thunderbird < 139.0.2.
References
security@mozilla.orghttps://bugzilla.mozilla.org/buglist.cgi?bug_id=1958580%2C1968012Broken Link
security@mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2025-49/Vendor Advisory
security@mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2025-50/Vendor Advisory
Impacted products
Vendor Product Version
Mozilla Thunderbird Version: unspecified   < 128.11.1
 Create a notification for this product.
   Mozilla Thunderbird Version: unspecified   < 139.0.2
 Create a notification for this product.
Show details on NVD website

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