CVE-2018-18509
Publication date 31 December 2018
Last updated 25 August 2025
Ubuntu priority
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.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| thunderbird | ||
| 18.04 LTS bionic |
Fixed 1:60.5.1+build2-0ubuntu0.18.04.1
|
|
| 16.04 LTS xenial |
Fixed 1:60.5.1+build2-0ubuntu0.16.04.1
|
|
| 14.04 LTS trusty |
Fixed 1:60.5.1+build2-0ubuntu0.14.04.1
|
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
5.3 · Medium
|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | None |
| Integrity impact | Low |
| Availability impact | None |
| Vector | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
References
Related Ubuntu Security Notices (USN)
- USN-3897-1
- Thunderbird vulnerabilities
- 26 February 2019