# RHSA-2020:4913: thunderbird security update

RHSA-2020:4913, released November 4, 2020, fixes 2 CVEs in thunderbird (version 0:78.4.0-1.el8_3). None of them is reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/fix/linux/rhsa-2020-4913
- Platform: Linux
- Released: Nov 4, 2020
- Priority: High (Closes CVE-2020-15683, high severity)
- CVEs: 2, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://access.redhat.com/errata/RHSA-2020:4913

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [thunderbird](https://patchblox.com/security/data/product/linux/thunderbird.md) | RHEL 8 | 0:78.4.0-1.el8_3 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2020-15683](https://patchblox.com/security/data/cve/CVE-2020-15683.md) | High | Firefox ESR and 2 others: Mozilla developers and community members reported memory safety bugs present in Firefox 81 and Firefox… | 9.8 | 0.0267 |  |
| [CVE-2020-15969](https://patchblox.com/security/data/cve/CVE-2020-15969.md) | High | firefox: Mozilla Firefox is an open-source web browser, designed for standards compliance, performance, and portability.  This... | 8.8 | 0.0174 |  |

---

Data as of 2026-11-07T06:34:28Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo