# RHSA-2021:4451: Security update for 7 packages

RHSA-2021:4451, released November 9, 2021, fixes 3 CVEs across 7 products. None of them is reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/fix/linux/rhsa-2021-4451
- Platform: Linux
- Released: Nov 9, 2021
- Priority: High (Closes CVE-2021-20231, high severity)
- CVEs: 3, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://access.redhat.com/errata/RHSA-2021:4451

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [gnutls](https://patchblox.com/security/data/product/linux/gnutls.md) | RHEL 8 | 0:3.6.16-4.el8 |
| [gnutls-c++](https://patchblox.com/security/data/product/linux/gnutls-c.md) | RHEL 8 | 0:3.6.16-4.el8 |
| [gnutls-dane](https://patchblox.com/security/data/product/linux/gnutls-dane.md) | RHEL 8 | 0:3.6.16-4.el8 |
| [gnutls-devel](https://patchblox.com/security/data/product/linux/gnutls-devel.md) | RHEL 8 | 0:3.6.16-4.el8 |
| [gnutls-utils](https://patchblox.com/security/data/product/linux/gnutls-utils.md) | RHEL 8 | 0:3.6.16-4.el8 |
| [nettle](https://patchblox.com/security/data/product/linux/nettle.md) | RHEL 8 | 0:3.4.1-7.el8 |
| [nettle-devel](https://patchblox.com/security/data/product/linux/nettle-devel.md) | RHEL 8 | 0:3.4.1-7.el8 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2021-20231](https://patchblox.com/security/data/cve/CVE-2021-20231.md) | High | gnutls: The gnutls packages provide the GNU Transport Layer Security (GnuTLS) library, which implements cryptographic algorit... | 9.8 | 0.0368 |  |
| [CVE-2021-20232](https://patchblox.com/security/data/cve/CVE-2021-20232.md) | High | gnutls: The gnutls packages provide the GNU Transport Layer Security (GnuTLS) library, which implements cryptographic algorit... | 9.8 | 0.0338 |  |
| [CVE-2021-3580](https://patchblox.com/security/data/cve/CVE-2021-3580.md) | High | gnutls: The gnutls packages provide the GNU Transport Layer Security (GnuTLS) library, which implements cryptographic algorit... | 7.5 | 0.0271 |  |

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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo