CVE-2018-18509 Information

Description

A flaw during verification of certain S/MIME signatures causes emails to be shown in Thunderbird as having a valid digital signature even if the shown message contents aren’t covered by the signature. The flaw allows an attacker to reuse a valid S/MIME signature to craft an email message with arbitrary content. This vulnerability affects Thunderbird 60.5.1.

CVSS Vector

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Reference

http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00043.html http://packetstormsecurity.com/files/152703/Johnny-You-Are-Fired.html http://seclists.org/fulldisclosure/2019/Apr/38 http://www.openwall.com/lists/oss-security/2019/04/30/4 https://access.redhat.com/errata/RHSA-2019:1144 https://bugzilla.mozilla.org/show_bug.cgi?id=1507218 https://github.com/RUB-NDS/Johnny-You-Are-Fired https://github.com/RUB-NDS/Johnny-You-Are-Fired/blob/master/paper/johnny-fired.pdf https://www.mozilla.org/security/advisories/mfsa2019-06/

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

LOW

Base Score

NONE

Base Severity

5.3