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.
The product does not verify, or incorrectly verifies, the cryptographic signature for data.
| Link | Tags |
|---|---|
| http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00043.html | vendor advisory |
| https://www.mozilla.org/security/advisories/mfsa2019-06/ | vendor advisory |
| https://bugzilla.mozilla.org/show_bug.cgi?id=1507218 | issue tracking permissions required vendor advisory |
| http://www.openwall.com/lists/oss-security/2019/04/30/4 | third party advisory mailing list |
| http://seclists.org/fulldisclosure/2019/Apr/38 | third party advisory mailing list |
| http://packetstormsecurity.com/files/152703/Johnny-You-Are-Fired.html | vdb entry third party advisory |
| https://access.redhat.com/errata/RHSA-2019:1144 | vendor advisory |
| https://github.com/RUB-NDS/Johnny-You-Are-Fired | |
| https://github.com/RUB-NDS/Johnny-You-Are-Fired/blob/master/paper/johnny-fired.pdf |