# RHSA-2020:5237: firefox security update

RHSA-2020:5237, released November 30, 2020, fixes 10 CVEs in firefox (version 0:78.5.0-1.el8_3). None of them is reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/fix/linux/rhsa-2020-5237
- Platform: Linux
- Released: Nov 30, 2020
- Priority: High (Closes CVE-2020-26960, high severity)
- CVEs: 10, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://access.redhat.com/errata/RHSA-2020:5237

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [firefox](https://patchblox.com/security/data/product/linux/firefox.md) | RHEL 8 | 0:78.5.0-1.el8_3 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2020-26960](https://patchblox.com/security/data/cve/CVE-2020-26960.md) | High | Firefox ESR and 2 others: If the Compact() method was called on an nsTArray, the array could have been reallocated without updating… | 8.8 | 0.0156 |  |
| [CVE-2020-26968](https://patchblox.com/security/data/cve/CVE-2020-26968.md) | High | Firefox ESR and 2 others: Mozilla developers reported memory safety bugs present in Firefox 82 and Firefox ESR 78.4. | 8.8 | 0.0151 |  |
| [CVE-2020-26959](https://patchblox.com/security/data/cve/CVE-2020-26959.md) | High | Firefox ESR and 2 others: During browser shutdown, reference decrementing could have occured on a previously freed object, resulting… | 8.8 | 0.0130 |  |
| [CVE-2020-16012](https://patchblox.com/security/data/cve/CVE-2020-16012.md) | Routine | Firefox ESR and 1 other: Side-channel information leakage in graphics in Google Chrome prior to 87.0.4280.66 allowed a remote… | 4.3 | 0.0257 |  |
| [CVE-2020-26958](https://patchblox.com/security/data/cve/CVE-2020-26958.md) | Routine | Firefox ESR and 2 others: Firefox did not block execution of scripts with incorrect MIME types when the response was intercepted… | 6.1 | 0.0136 |  |
| [CVE-2020-26953](https://patchblox.com/security/data/cve/CVE-2020-26953.md) | Routine | Firefox ESR and 2 others: It was possible to cause the browser to enter fullscreen mode without displaying the security UI; thus… | 4.3 | 0.0129 |  |
| [CVE-2020-26965](https://patchblox.com/security/data/cve/CVE-2020-26965.md) | Routine | Firefox ESR and 2 others: Some websites have a feature "Show Password" where clicking a button will change a password field into… | 6.5 | 0.0126 |  |
| [CVE-2020-26956](https://patchblox.com/security/data/cve/CVE-2020-26956.md) | Routine | Firefox ESR and 2 others: In some cases, removing HTML elements during sanitization would keep existing SVG event handlers and… | 6.1 | 0.0123 |  |
| [CVE-2020-26961](https://patchblox.com/security/data/cve/CVE-2020-26961.md) | Routine | Firefox ESR and 2 others: When DNS over HTTPS is in use, it intentionally filters RFC1918 and related IP ranges from the responses… | 6.5 | 0.0117 |  |
| [CVE-2020-26951](https://patchblox.com/security/data/cve/CVE-2020-26951.md) | Routine | Firefox ESR and 2 others: A parsing and event loading mismatch in Firefox's SVG code could have allowed load events to fire, even… | 6.1 | 0.0105 |  |

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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