CVE-2025-5986

Name
CVE-2025-5986
Description
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.
NVD Severity
unknown
Other trackers
CVE, NVD, CERT, CVE Details, CIRCL, Arch Linux, Debian, Red Hat, Ubuntu, Gentoo, SUSE (Bugzilla), SUSE (CVE), Mageia
Mailing lists
oss-security, full-disclosure, bugtraq
Exploits
Exploit DB, Metasploit
Forges
GitHub (code, issues), Aports (code, issues)

References

Type URI
security@mozilla.org https://bugzilla.mozilla.org/buglist.cgi?bug_id=1958580%2C1968012
security@mozilla.org https://www.mozilla.org/security/advisories/mfsa2025-49/
security@mozilla.org https://www.mozilla.org/security/advisories/mfsa2025-50/
af854a3a-2127-422b-91ae-364da2661108 https://lists.debian.org/debian-lts-announce/2025/07/msg00002.html

Match rules

CPE URI Source package Min version Max version
thunderbird >= unspecified < 128.11.1
thunderbird >= unspecified < 139.0.2

Vulnerable and fixed packages

Source package Branch Version Maintainer Status
thunderbird edge-community 128.5.1-r0 Patrycja Rosa <alpine@ptrcnull.me> possibly vulnerable
thunderbird edge-community 128.5.2-r0 Patrycja Rosa <alpine@ptrcnull.me> possibly vulnerable
thunderbird edge-community 128.6.0-r0 Patrycja Rosa <alpine@ptrcnull.me> possibly vulnerable
thunderbird edge-community 128.7.0-r0 Patrycja Rosa <alpine@ptrcnull.me> possibly vulnerable
thunderbird edge-community 128.7.1-r0 Patrycja Rosa <alpine@ptrcnull.me> possibly vulnerable
thunderbird edge-community 128.8.0-r0 Patrycja Rosa <alpine@ptrcnull.me> possibly vulnerable
thunderbird edge-community 137.0-r0 Patrycja Rosa <alpine@ptrcnull.me> possibly vulnerable
thunderbird edge-community 137.0.1-r0 Patrycja Rosa <alpine@ptrcnull.me> possibly vulnerable
thunderbird edge-community 138.0-r0 Patrycja Rosa <alpine@ptrcnull.me> possibly vulnerable
thunderbird edge-community 138.0-r1 Patrycja Rosa <alpine@ptrcnull.me> possibly vulnerable
thunderbird edge-community 138.0-r2 Patrycja Rosa <alpine@ptrcnull.me> possibly vulnerable
thunderbird 3.22-community 128.11.0-r0 Patrycja Rosa <alpine@ptrcnull.me> possibly vulnerable