# RHSA-2020:4756: Security update for 4 packages

RHSA-2020:4756, released November 4, 2020, fixes 3 CVEs across 4 products. None of them is reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/fix/linux/rhsa-2020-4756
- Platform: Linux
- Released: Nov 4, 2020
- Priority: High (Closes CVE-2019-15892, high severity)
- CVEs: 3, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://access.redhat.com/errata/RHSA-2020:4756

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [varnish](https://patchblox.com/security/data/product/linux/varnish.md) | RHEL 8 | 0:6.0.6-2.module+el8.3.0+6843+b3b42fcc |
| [varnish-devel](https://patchblox.com/security/data/product/linux/varnish-devel.md) | RHEL 8 | 0:6.0.6-2.module+el8.3.0+6843+b3b42fcc |
| [varnish-docs](https://patchblox.com/security/data/product/linux/varnish-docs.md) | RHEL 8 | 0:6.0.6-2.module+el8.3.0+6843+b3b42fcc |
| [varnish-modules](https://patchblox.com/security/data/product/linux/varnish-modules.md) | RHEL 8 | 0:0.15.0-5.module+el8.3.0+6843+b3b42fcc |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2019-15892](https://patchblox.com/security/data/cve/CVE-2019-15892.md) | High | varnish: Varnish Cache is a high-performance HTTP accelerator | 7.5 | 0.0590 |  |
| [CVE-2020-11653](https://patchblox.com/security/data/cve/CVE-2020-11653.md) | High | varnish: Varnish Cache is a high-performance HTTP accelerator | 7.5 | 0.0216 |  |
| [CVE-2019-20637](https://patchblox.com/security/data/cve/CVE-2019-20637.md) | High | varnish: Varnish Cache is a high-performance HTTP accelerator | 7.5 | 0.0179 |  |

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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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo