FreeBSD 12.1-RELEASE Errata

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Last modified on 2019-11-22 18:48:16 by gjb.

This document lists errata items for FreeBSD 12.1-RELEASE, containing significant information discovered after the release or too late in the release cycle to be otherwise included in the release documentation. This information includes security advisories, as well as news relating to the software or documentation that could affect its operation or usability. An up-to-date version of this document should always be consulted before installing this version of FreeBSD.

This errata document for FreeBSD 12.1-RELEASE will be maintained until the release of FreeBSD 12.2-RELEASE.

Table of Contents
1. Introduction
2. Security Advisories
3. Errata Notices
4. Open Issues
5. Late-Breaking News

1. Introduction

This errata document contains late-breaking news about FreeBSD 12.1-RELEASE Before installing this version, it is important to consult this document to learn about any post-release discoveries or problems that may already have been found and fixed.

Any version of this errata document actually distributed with the release (for example, on a CDROM distribution) will be out of date by definition, but other copies are kept updated on the Internet and should be consulted as the current errata for this release. These other copies of the errata are located at, plus any sites which keep up-to-date mirrors of this location.

Source and binary snapshots of FreeBSD 12-STABLE also contain up-to-date copies of this document (as of the time of the snapshot).

For a list of all FreeBSD CERT security advisories, see

2. Security Advisories

FreeBSD-SA-19:25.mcepce12 November 2019

Machine Check Exception on Page Size Change

FreeBSD-SA-19:26.mcu12 November 2019

Intel CPU Microcode Update

FreeBSD-SA-20:01.libfetch28 January 2020

fetch(3) buffer overflow

FreeBSD-SA-20:03.thrmisc28 January 2020

Kernel stack data disclosure

3. Errata Notices

FreeBSD-EN-19:19.loader12 November 2019

UEFI Loader Memory Fragmentation

FreeBSD-EN-20:01.ssp28 January 2020

Imprecise orderring of canary initialization

4. Open Issues

  • [2019-11-04] A late issue was discovered where systems using the graphics/drm-kmod port built on FreeBSD 12.0-RELEASE will crash during boot. It is advised to remove the port prior to upgrading, and build the port instead of using the upstream binary package.

5. Late-Breaking News

  • [2019-11-22] The FreeBSD 12.1-RELEASE announcement includes mention of FreeBSD/amd64 Amazon® EC2™ AMIs (Amazon Machine Images). Though it also included mention of FreeBSD/aarch64 being available in various regions, it had not passed third-party validation for inclusion in the Amazon® Marketplace.

    FreeBSD 12.1-RELEASE aarch64 Amazon® EC2™ AMIs are now available in the Marketplace here.