Skip to navigation Skip to main content

Utilities

  • Subscriptions
  • Downloads
  • Red Hat Console
  • Get Support
Red Hat Customer Portal
  • Subscriptions
  • Downloads
  • Red Hat Console
  • Get Support
  • Products

    Top Products

    • Red Hat Enterprise Linux
    • Red Hat OpenShift
    • Red Hat Ansible Automation Platform
    All Products

    Downloads and Containers

    • Downloads
    • Packages
    • Containers

    Top Resources

    • Documentation
    • Product Life Cycles
    • Product Compliance
    • Errata
  • Knowledge

    Red Hat Knowledge Center

    • Knowledgebase Solutions
    • Knowledgebase Articles
    • Customer Portal Labs
    • Errata

    Top Product Docs

    • Red Hat Enterprise Linux
    • Red Hat OpenShift
    • Red Hat Ansible Automation Platform
    All Product Docs

    Training and Certification

    • About
    • Course Index
    • Certification Index
    • Skill Assessment
  • Security

    Red Hat Product Security Center

    • Security Updates
    • Security Advisories
    • Red Hat CVE Database
    • Errata

    References

    • Security Bulletins
    • Security Measurement
    • Severity Ratings
    • Security Data

    Top Resources

    • Security Labs
    • Backporting Policies
    • Security Blog
  • Support

    Red Hat Support

    • Support Cases
    • Troubleshoot
    • Get Support
    • Contact Red Hat Support

    Red Hat Community Support

    • Customer Portal Community
    • Community Discussions
    • Red Hat Accelerator Program

    Top Resources

    • Product Life Cycles
    • Customer Portal Labs
    • Red Hat JBoss Supported Configurations
    • Red Hat Insights
Or troubleshoot an issue.

Select Your Language

  • English
  • Français
  • 한국어
  • 日本語
  • 中文 (中国)

Infrastructure and Management

  • Red Hat Enterprise Linux
  • Red Hat Satellite
  • Red Hat Subscription Management
  • Red Hat Insights
  • Red Hat Ansible Automation Platform

Cloud Computing

  • Red Hat OpenShift
  • Red Hat OpenStack Platform
  • Red Hat OpenShift
  • Red Hat OpenShift AI
  • Red Hat OpenShift Dedicated
  • Red Hat Advanced Cluster Security for Kubernetes
  • Red Hat Advanced Cluster Management for Kubernetes
  • Red Hat Quay
  • Red Hat OpenShift Dev Spaces
  • Red Hat OpenShift Service on AWS

Storage

  • Red Hat Gluster Storage
  • Red Hat Hyperconverged Infrastructure
  • Red Hat Ceph Storage
  • Red Hat OpenShift Data Foundation

Runtimes

  • Red Hat Runtimes
  • Red Hat JBoss Enterprise Application Platform
  • Red Hat Data Grid
  • Red Hat JBoss Web Server
  • Red Hat build of Keycloak
  • Red Hat support for Spring Boot
  • Red Hat build of Node.js
  • Red Hat build of Quarkus

Integration and Automation

  • Red Hat Application Foundations
  • Red Hat Fuse
  • Red Hat AMQ
  • Red Hat 3scale API Management
All Products
Red Hat Product Errata RHSA-2021:0299 - Security Advisory
Issued:
2021-01-28
Updated:
2021-01-28

RHSA-2021:0299 - Security Advisory

  • Overview
  • Updated Packages

Synopsis

Important: thunderbird security update

Type/Severity

Security Advisory: Important

Red Hat Insights patch analysis

Identify and remediate systems affected by this advisory.

View affected systems

Topic

An update for thunderbird is now available for Red Hat Enterprise Linux 8.2 Extended Update Support.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

Mozilla Thunderbird is a standalone mail and newsgroup client.

This update upgrades Thunderbird to version 78.7.0.

Security Fix(es):

  • Mozilla: Cross-origin information leakage via redirected PDF requests (CVE-2021-23953)
  • Mozilla: Type confusion when using logical assignment operators in JavaScript switch statements (CVE-2021-23954)
  • Mozilla: Memory safety bugs fixed in Firefox 85 and Firefox ESR 78.7 (CVE-2021-23964)
  • Mozilla: IMAP Response Injection when using STARTTLS (CVE-2020-15685)
  • Mozilla: HTTPS pages could have been intercepted by a registered service worker when they should not have been (CVE-2020-26976)
  • Mozilla: Use-after-poison for incorrectly redeclared JavaScript variables during GC (CVE-2021-23960)

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.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

All running instances of Thunderbird must be restarted for the update to take effect.

Affected Products

  • Red Hat Enterprise Linux for x86_64 - Extended Update Support 8.2 x86_64
  • Red Hat Enterprise Linux Server - AUS 8.2 x86_64
  • Red Hat Enterprise Linux for Power, little endian - Extended Update Support 8.2 ppc64le
  • Red Hat Enterprise Linux Server - TUS 8.2 x86_64
  • Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.2 aarch64
  • Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.2 ppc64le
  • Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.2 x86_64

Fixes

  • BZ - 1920646 - CVE-2021-23953 Mozilla: Cross-origin information leakage via redirected PDF requests
  • BZ - 1920648 - CVE-2021-23954 Mozilla: Type confusion when using logical assignment operators in JavaScript switch statements
  • BZ - 1920649 - CVE-2020-26976 Mozilla: HTTPS pages could have been intercepted by a registered service worker when they should not have been
  • BZ - 1920650 - CVE-2021-23960 Mozilla: Use-after-poison for incorrectly redeclared JavaScript variables during GC
  • BZ - 1920651 - CVE-2021-23964 Mozilla: Memory safety bugs fixed in Firefox 85 and Firefox ESR 78.7
  • BZ - 1921543 - CVE-2020-15685 Mozilla: IMAP Response Injection when using STARTTLS

CVEs

  • CVE-2020-15685
  • CVE-2020-26976
  • CVE-2021-23953
  • CVE-2021-23954
  • CVE-2021-23960
  • CVE-2021-23964

References

  • https://access.redhat.com/security/updates/classification/#important
Note: More recent versions of these packages may be available. Click a package name for more details.

Red Hat Enterprise Linux for x86_64 - Extended Update Support 8.2

SRPM
thunderbird-78.7.0-1.el8_2.src.rpm SHA-256: 45d4e48ea5996da382a3cbd026cfd61a67c8d7c13ad8d66d361db97d33864eeb
x86_64
thunderbird-78.7.0-1.el8_2.x86_64.rpm SHA-256: 8aaa5fe7d74ec9975462441ac1f658faaca6729e92a3118833d0e8ebb13d8e5f
thunderbird-debuginfo-78.7.0-1.el8_2.x86_64.rpm SHA-256: 3ef8550916e2565579e9985c8122adaca443a2b99743e11dfedcb6767eb9b82f
thunderbird-debugsource-78.7.0-1.el8_2.x86_64.rpm SHA-256: 2ddb512acdaf4511974ce71c14e75d68e23efe2b8a5e8aee0fc5f566b040e744

Red Hat Enterprise Linux Server - AUS 8.2

SRPM
thunderbird-78.7.0-1.el8_2.src.rpm SHA-256: 45d4e48ea5996da382a3cbd026cfd61a67c8d7c13ad8d66d361db97d33864eeb
x86_64
thunderbird-78.7.0-1.el8_2.x86_64.rpm SHA-256: 8aaa5fe7d74ec9975462441ac1f658faaca6729e92a3118833d0e8ebb13d8e5f
thunderbird-debuginfo-78.7.0-1.el8_2.x86_64.rpm SHA-256: 3ef8550916e2565579e9985c8122adaca443a2b99743e11dfedcb6767eb9b82f
thunderbird-debugsource-78.7.0-1.el8_2.x86_64.rpm SHA-256: 2ddb512acdaf4511974ce71c14e75d68e23efe2b8a5e8aee0fc5f566b040e744

Red Hat Enterprise Linux for Power, little endian - Extended Update Support 8.2

SRPM
thunderbird-78.7.0-1.el8_2.src.rpm SHA-256: 45d4e48ea5996da382a3cbd026cfd61a67c8d7c13ad8d66d361db97d33864eeb
ppc64le
thunderbird-78.7.0-1.el8_2.ppc64le.rpm SHA-256: 32d32bfa78bb7c1e6fd7a1d12baf4315b6b91ae240ffdabac4c49dca382ca1b0
thunderbird-debuginfo-78.7.0-1.el8_2.ppc64le.rpm SHA-256: da4e282aa2152dbc3afd615a8eec3ba06bb8b50776bfa98aa96754960b8deece
thunderbird-debugsource-78.7.0-1.el8_2.ppc64le.rpm SHA-256: 9a13602930b82c6205eeb3d431b67cb08203cac2b688c085a0277a024e7c431c

Red Hat Enterprise Linux Server - TUS 8.2

SRPM
thunderbird-78.7.0-1.el8_2.src.rpm SHA-256: 45d4e48ea5996da382a3cbd026cfd61a67c8d7c13ad8d66d361db97d33864eeb
x86_64
thunderbird-78.7.0-1.el8_2.x86_64.rpm SHA-256: 8aaa5fe7d74ec9975462441ac1f658faaca6729e92a3118833d0e8ebb13d8e5f
thunderbird-debuginfo-78.7.0-1.el8_2.x86_64.rpm SHA-256: 3ef8550916e2565579e9985c8122adaca443a2b99743e11dfedcb6767eb9b82f
thunderbird-debugsource-78.7.0-1.el8_2.x86_64.rpm SHA-256: 2ddb512acdaf4511974ce71c14e75d68e23efe2b8a5e8aee0fc5f566b040e744

Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.2

SRPM
thunderbird-78.7.0-1.el8_2.src.rpm SHA-256: 45d4e48ea5996da382a3cbd026cfd61a67c8d7c13ad8d66d361db97d33864eeb
aarch64
thunderbird-78.7.0-1.el8_2.aarch64.rpm SHA-256: a6652efef682ab7e1972d2b3aa74ce03b9c570a442eaabbf14442c042d023599
thunderbird-debuginfo-78.7.0-1.el8_2.aarch64.rpm SHA-256: 291e028bf4aed667718a593bfa7425f370eabbf61b7b8492b5a274cfe7f4c9ee
thunderbird-debugsource-78.7.0-1.el8_2.aarch64.rpm SHA-256: 360850b7c6b8d8ffab4d84bcbb4d0aaabe0030c641efed9bc24cafcf5e758aaf

Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.2

SRPM
thunderbird-78.7.0-1.el8_2.src.rpm SHA-256: 45d4e48ea5996da382a3cbd026cfd61a67c8d7c13ad8d66d361db97d33864eeb
ppc64le
thunderbird-78.7.0-1.el8_2.ppc64le.rpm SHA-256: 32d32bfa78bb7c1e6fd7a1d12baf4315b6b91ae240ffdabac4c49dca382ca1b0
thunderbird-debuginfo-78.7.0-1.el8_2.ppc64le.rpm SHA-256: da4e282aa2152dbc3afd615a8eec3ba06bb8b50776bfa98aa96754960b8deece
thunderbird-debugsource-78.7.0-1.el8_2.ppc64le.rpm SHA-256: 9a13602930b82c6205eeb3d431b67cb08203cac2b688c085a0277a024e7c431c

Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.2

SRPM
thunderbird-78.7.0-1.el8_2.src.rpm SHA-256: 45d4e48ea5996da382a3cbd026cfd61a67c8d7c13ad8d66d361db97d33864eeb
x86_64
thunderbird-78.7.0-1.el8_2.x86_64.rpm SHA-256: 8aaa5fe7d74ec9975462441ac1f658faaca6729e92a3118833d0e8ebb13d8e5f
thunderbird-debuginfo-78.7.0-1.el8_2.x86_64.rpm SHA-256: 3ef8550916e2565579e9985c8122adaca443a2b99743e11dfedcb6767eb9b82f
thunderbird-debugsource-78.7.0-1.el8_2.x86_64.rpm SHA-256: 2ddb512acdaf4511974ce71c14e75d68e23efe2b8a5e8aee0fc5f566b040e744

The Red Hat security contact is secalert@redhat.com. More contact details at https://access.redhat.com/security/team/contact/.

Red Hat LinkedIn YouTube Facebook X, formerly Twitter

Quick Links

  • Downloads
  • Subscriptions
  • Support Cases
  • Customer Service
  • Product Documentation

Help

  • Contact Us
  • Customer Portal FAQ
  • Log-in Assistance

Site Info

  • Trust Red Hat
  • Browser Support Policy
  • Accessibility
  • Awards and Recognition
  • Colophon

Related Sites

  • redhat.com
  • developers.redhat.com
  • connect.redhat.com
  • cloud.redhat.com

Red Hat legal and privacy links

  • About Red Hat
  • Jobs
  • Events
  • Locations
  • Contact Red Hat
  • Red Hat Blog
  • Inclusion at Red Hat
  • Cool Stuff Store
  • Red Hat Summit
© 2025 Red Hat, Inc.

Red Hat legal and privacy links

  • Privacy statement
  • Terms of use
  • All policies and guidelines
  • Digital accessibility