# CVE-2018-18509: thunderbird: A flaw during verification of certain S/MIME signatures causes emails to be shown in Thunderbird as having a valid di...

CVE-2018-18509 is fixed in 8 products on 1 platform, first by thunderbird 1:60.5.1+build2-0ubuntu0.18.04.1, released February 13, 2019. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2018-18509
- Priority: Routine
- CVSS: 5.3 (Medium)
- EPSS: 0.0168
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Dec 30, 2018

## 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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | thunderbird RHEL 8 | 0:60.6.1-1.el8 | [RHSA-2019:1144](https://patchblox.com/security/data/fix/linux/rhsa-2019-1144.md) | May 13, 2019 |
| Linux | thunderbird Ubuntu 18.04.6 LTS (bionic) | 1:60.5.1+build2-0ubuntu0.18.04.1 | [thunderbird 1:60.5.1+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-1-60.5.1-build2-0ubuntu0.18.04.1.md) | Feb 13, 2019 |
| Linux | thunderbird-globalmenu Ubuntu 18.04.6 LTS (bionic) | 1:60.5.1+build2-0ubuntu0.18.04.1 | [thunderbird-globalmenu 1:60.5.1+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-globalmenu-1-60.5.1-build2-0ubuntu0.18.04.1.md) | Feb 13, 2019 |
| Linux | thunderbird-gnome-support Ubuntu 18.04.6 LTS (bionic) | 1:60.5.1+build2-0ubuntu0.18.04.1 | [thunderbird-gnome-support 1:60.5.1+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-gnome-support-1-60.5.1-build2-0ubuntu0.18.04.1.md) | Feb 13, 2019 |
| Linux | thunderbird-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 1:60.5.1+build2-0ubuntu0.18.04.1 | [thunderbird-mozsymbols 1:60.5.1+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-mozsymbols-1-60.5.1-build2-0ubuntu0.18.04.1.md) | Feb 13, 2019 |
| Linux | thunderbird-testsuite Ubuntu 18.04.6 LTS (bionic) | 1:60.5.1+build2-0ubuntu0.18.04.1 | [thunderbird-testsuite 1:60.5.1+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-testsuite-1-60.5.1-build2-0ubuntu0.18.04.1.md) | Feb 13, 2019 |
| Linux | xul-ext-calendar-timezones Ubuntu 18.04.6 LTS (bionic) | 1:60.5.1+build2-0ubuntu0.18.04.1 | [xul-ext-calendar-timezones 1:60.5.1+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-calendar-timezones-1-60.5.1-build2-0ubuntu0.18.04.1.md) | Feb 13, 2019 |
| Linux | xul-ext-gdata-provider Ubuntu 18.04.6 LTS (bionic) | 1:60.5.1+build2-0ubuntu0.18.04.1 | [xul-ext-gdata-provider 1:60.5.1+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-gdata-provider-1-60.5.1-build2-0ubuntu0.18.04.1.md) | Feb 13, 2019 |
| Linux | xul-ext-lightning Ubuntu 18.04.6 LTS (bionic) | 1:60.5.1+build2-0ubuntu0.18.04.1 | [xul-ext-lightning 1:60.5.1+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-lightning-1-60.5.1-build2-0ubuntu0.18.04.1.md) | Feb 13, 2019 |

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