# RHSA-2020:5624: thunderbird security update

RHSA-2020:5624, released December 17, 2020, fixes 7 CVEs in thunderbird (version 0:78.6.0-1.el8_3). None of them is reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/fix/linux/rhsa-2020-5624
- Platform: Linux
- Released: Dec 17, 2020
- Priority: High (Closes CVE-2020-26971, high severity)
- CVEs: 7, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://access.redhat.com/errata/RHSA-2020:5624

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [thunderbird](https://patchblox.com/security/data/product/linux/thunderbird.md) | RHEL 8 | 0:78.6.0-1.el8_3 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2020-26971](https://patchblox.com/security/data/cve/CVE-2020-26971.md) | High | Firefox ESR and 2 others: Certain blit values provided by the user were not properly constrained leading to a heap buffer overflow… | 8.8 | 0.0190 |  |
| [CVE-2020-26973](https://patchblox.com/security/data/cve/CVE-2020-26973.md) | High | Firefox ESR and 2 others: Certain input to the CSS Sanitizer confused it, resulting in incorrect components being removed. | 8.8 | 0.0162 |  |
| [CVE-2020-35113](https://patchblox.com/security/data/cve/CVE-2020-35113.md) | High | Firefox ESR and 2 others: Mozilla developers reported memory safety bugs present in Firefox 83 and Firefox ESR 78.5. | 8.8 | 0.0157 |  |
| [CVE-2020-26974](https://patchblox.com/security/data/cve/CVE-2020-26974.md) | High | Firefox ESR and 2 others: When flex-basis was used on a table wrapper, a StyleGenericFlexBasis object could have been incorrectly… | 8.8 | 0.0153 |  |
| [CVE-2020-35111](https://patchblox.com/security/data/cve/CVE-2020-35111.md) | Routine | Firefox ESR and 2 others: When an extension with the proxy permission registered to receive <all_urls>, the proxy.onRequest callback… | 4.3 | 0.0143 |  |
| [CVE-2020-26978](https://patchblox.com/security/data/cve/CVE-2020-26978.md) | Routine | Firefox ESR and 2 others: Using techniques that built on the slipstream research, a malicious webpage could have exposed both an… | 6.1 | 0.0133 |  |
| [CVE-2020-16042](https://patchblox.com/security/data/cve/CVE-2020-16042.md) | Routine | firefox: Mozilla Firefox is an open-source web browser, designed for standards compliance, performance, and portability.  This... | 6.5 | 0.0111 |  |

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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