# CVE-2021-3571: linuxptp: The linuxptp packages provide Precision Time Protocol (PTP) implementation for Linux according to IEEE standard 1588...

CVE-2021-3571 is fixed in linuxptp on 1 platform, first by RHSA-2021:4321, released November 9, 2021. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-3571
- Priority: High
- CVSS: 7.1 (Moderate)
- EPSS: 0.0190
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Nov 9, 2021

## Description

The linuxptp packages provide Precision Time Protocol (PTP) implementation for Linux according to IEEE standard 1588 for Linux. The dual design goals are to provide a robust implementation of the standard and to use the most relevant and modern Application Programming Interfaces (API) offered by the Linux kernel.   The following packages have been upgraded to a later upstream version: linuxptp (3.1.1). (BZ#1895005)  Security Fix(es):  * linuxptp: wrong length of one-step follow-up in transparent clock (CVE-2021-3571)  For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.  Additional Changes:  For detailed information on changes in this release, see the Red Hat Enterprise Linux 8.5 Release Notes linked from the References section.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linuxptp RHEL 8 | 0:3.1.1-1.el8 | [RHSA-2021:4321](https://patchblox.com/security/data/fix/linux/rhsa-2021-4321.md) | Nov 9, 2021 |
| Linux | linuxptp almalinux 8 | 3.1.1-1.el8 | [ALSA-2021:4321](https://patchblox.com/security/data/fix/linux/alsa-2021-4321.md) | Nov 9, 2021 |
| Linux | linuxptp ol 8 | 0:3.1.1-1.el8 | [ELSA-2021-4321](https://patchblox.com/security/data/fix/linux/elsa-2021-4321.md) | Nov 16, 2021 |
| Linux | linuxptp rocky 8 | 0:3.1.1-1.el8 | [RLSA-2021:4321](https://patchblox.com/security/data/fix/linux/rlsa-2021-4321.md) | Nov 9, 2021 |

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