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Red Hat Product Errata RHSA-2021:0992 - Security Advisory
Issued:
2021-03-25
Updated:
2021-03-25

RHSA-2021:0992 - Security Advisory

  • Overview
  • Updated Packages

Synopsis

Important: firefox security update

Type/Severity

Security Advisory: Important

Red Hat Lightspeed patch analysis

Identify and remediate systems affected by this advisory.

View affected systems

Topic

An update for firefox is now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having a security impact of Critical. 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 Firefox is an open-source web browser, designed for standards compliance, performance, and portability.

This update upgrades Firefox to version 78.9.0 ESR.

Security Fix(es):

  • Mozilla: Texture upload into an unbound backing buffer resulted in an out-of-bound read (CVE-2021-23981)
  • Mozilla: Memory safety bugs fixed in Firefox 87 and Firefox ESR 78.9 (CVE-2021-23987)
  • Mozilla: Internal network hosts could have been probed by a malicious webpage (CVE-2021-23982)
  • Mozilla: Malicious extensions could have spoofed popup information (CVE-2021-23984)

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

After installing the update, Firefox must be restarted for the changes to take effect.

Affected Products

  • Red Hat Enterprise Linux Server 7 x86_64
  • Red Hat Enterprise Linux Server - Extended Life Cycle Support 7 x86_64
  • Red Hat Enterprise Linux Workstation 7 x86_64
  • Red Hat Enterprise Linux Desktop 7 x86_64
  • Red Hat Enterprise Linux for IBM z Systems 7 s390x
  • Red Hat Enterprise Linux for Power, big endian 7 ppc64
  • Red Hat Enterprise Linux for Power, little endian 7 ppc64le
  • Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 7 s390x
  • Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, big endian 7 ppc64
  • Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, little endian 7 ppc64le

Fixes

  • BZ - 1942783 - CVE-2021-23981 Mozilla: Texture upload into an unbound backing buffer resulted in an out-of-bound read
  • BZ - 1942785 - CVE-2021-23982 Mozilla: Internal network hosts could have been probed by a malicious webpage
  • BZ - 1942786 - CVE-2021-23984 Mozilla: Malicious extensions could have spoofed popup information
  • BZ - 1942787 - CVE-2021-23987 Mozilla: Memory safety bugs fixed in Firefox 87 and Firefox ESR 78.9

CVEs

  • CVE-2021-4127
  • CVE-2021-23981
  • CVE-2021-23982
  • CVE-2021-23984
  • CVE-2021-23987

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 Server 7

SRPM
firefox-78.9.0-1.el7_9.src.rpm SHA-256: d8b886c11e7c40e1f588e3f4ed39010848cdb1aa89b9eebfa54c5435821f3aef
x86_64
firefox-78.9.0-1.el7_9.i686.rpm SHA-256: baae4611d00934d9db0d190375a9ef31da209123eed5b73d0fadb3786d2fd5d4
firefox-78.9.0-1.el7_9.x86_64.rpm SHA-256: 25c70dd5afe7477f9f048bb002f21d904277100207dc89d7030a2f3482e0469b
firefox-debuginfo-78.9.0-1.el7_9.x86_64.rpm SHA-256: 2fa4892f43ef9b7304545f2b73a542aaa35927e678248d096b30f9a76fdce7c9

Red Hat Enterprise Linux Server - Extended Life Cycle Support 7

SRPM
firefox-78.9.0-1.el7_9.src.rpm SHA-256: d8b886c11e7c40e1f588e3f4ed39010848cdb1aa89b9eebfa54c5435821f3aef
x86_64
firefox-78.9.0-1.el7_9.i686.rpm SHA-256: baae4611d00934d9db0d190375a9ef31da209123eed5b73d0fadb3786d2fd5d4
firefox-78.9.0-1.el7_9.x86_64.rpm SHA-256: 25c70dd5afe7477f9f048bb002f21d904277100207dc89d7030a2f3482e0469b
firefox-debuginfo-78.9.0-1.el7_9.x86_64.rpm SHA-256: 2fa4892f43ef9b7304545f2b73a542aaa35927e678248d096b30f9a76fdce7c9

Red Hat Enterprise Linux Workstation 7

SRPM
firefox-78.9.0-1.el7_9.src.rpm SHA-256: d8b886c11e7c40e1f588e3f4ed39010848cdb1aa89b9eebfa54c5435821f3aef
x86_64
firefox-78.9.0-1.el7_9.i686.rpm SHA-256: baae4611d00934d9db0d190375a9ef31da209123eed5b73d0fadb3786d2fd5d4
firefox-78.9.0-1.el7_9.x86_64.rpm SHA-256: 25c70dd5afe7477f9f048bb002f21d904277100207dc89d7030a2f3482e0469b
firefox-debuginfo-78.9.0-1.el7_9.x86_64.rpm SHA-256: 2fa4892f43ef9b7304545f2b73a542aaa35927e678248d096b30f9a76fdce7c9

Red Hat Enterprise Linux Desktop 7

SRPM
firefox-78.9.0-1.el7_9.src.rpm SHA-256: d8b886c11e7c40e1f588e3f4ed39010848cdb1aa89b9eebfa54c5435821f3aef
x86_64
firefox-78.9.0-1.el7_9.i686.rpm SHA-256: baae4611d00934d9db0d190375a9ef31da209123eed5b73d0fadb3786d2fd5d4
firefox-78.9.0-1.el7_9.x86_64.rpm SHA-256: 25c70dd5afe7477f9f048bb002f21d904277100207dc89d7030a2f3482e0469b
firefox-debuginfo-78.9.0-1.el7_9.x86_64.rpm SHA-256: 2fa4892f43ef9b7304545f2b73a542aaa35927e678248d096b30f9a76fdce7c9

Red Hat Enterprise Linux for IBM z Systems 7

SRPM
firefox-78.9.0-1.el7_9.src.rpm SHA-256: d8b886c11e7c40e1f588e3f4ed39010848cdb1aa89b9eebfa54c5435821f3aef
s390x
firefox-78.9.0-1.el7_9.s390x.rpm SHA-256: 48e3cefb854158ddd7565e9a4ae498d875af1e8446fc3ec07f019a3df9b9d668
firefox-debuginfo-78.9.0-1.el7_9.s390x.rpm SHA-256: 259004b417a389e8e2e5af02cca54eb8054d48bd37ad0e0cf496d5aed2866ebd

Red Hat Enterprise Linux for Power, big endian 7

SRPM
firefox-78.9.0-1.el7_9.src.rpm SHA-256: d8b886c11e7c40e1f588e3f4ed39010848cdb1aa89b9eebfa54c5435821f3aef
ppc64
firefox-78.9.0-1.el7_9.ppc64.rpm SHA-256: a2b632957b2840bd5af3c7d7dd7f8a97640a24fdda16cf399a2134a9fcc791db
firefox-debuginfo-78.9.0-1.el7_9.ppc64.rpm SHA-256: 37c0f24a5b0d0719d038330dfb45732fd2a1158151172f89d03784d73efe5089

Red Hat Enterprise Linux for Power, little endian 7

SRPM
firefox-78.9.0-1.el7_9.src.rpm SHA-256: d8b886c11e7c40e1f588e3f4ed39010848cdb1aa89b9eebfa54c5435821f3aef
ppc64le
firefox-78.9.0-1.el7_9.ppc64le.rpm SHA-256: 37ef4fec1fa218b532acfd7e13844289d61c440686c23fd7fe60ff641da3f533
firefox-debuginfo-78.9.0-1.el7_9.ppc64le.rpm SHA-256: 0edf80dcacc02f039d7e37ba3f8bae765f0fdd6c4a3a8171e582e0a78f09654b

Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 7

SRPM
firefox-78.9.0-1.el7_9.src.rpm SHA-256: d8b886c11e7c40e1f588e3f4ed39010848cdb1aa89b9eebfa54c5435821f3aef
s390x
firefox-78.9.0-1.el7_9.s390x.rpm SHA-256: 48e3cefb854158ddd7565e9a4ae498d875af1e8446fc3ec07f019a3df9b9d668
firefox-debuginfo-78.9.0-1.el7_9.s390x.rpm SHA-256: 259004b417a389e8e2e5af02cca54eb8054d48bd37ad0e0cf496d5aed2866ebd

Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, big endian 7

SRPM
firefox-78.9.0-1.el7_9.src.rpm SHA-256: d8b886c11e7c40e1f588e3f4ed39010848cdb1aa89b9eebfa54c5435821f3aef
ppc64
firefox-78.9.0-1.el7_9.ppc64.rpm SHA-256: a2b632957b2840bd5af3c7d7dd7f8a97640a24fdda16cf399a2134a9fcc791db
firefox-debuginfo-78.9.0-1.el7_9.ppc64.rpm SHA-256: 37c0f24a5b0d0719d038330dfb45732fd2a1158151172f89d03784d73efe5089

Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, little endian 7

SRPM
firefox-78.9.0-1.el7_9.src.rpm SHA-256: d8b886c11e7c40e1f588e3f4ed39010848cdb1aa89b9eebfa54c5435821f3aef
ppc64le
firefox-78.9.0-1.el7_9.ppc64le.rpm SHA-256: 37ef4fec1fa218b532acfd7e13844289d61c440686c23fd7fe60ff641da3f533
firefox-debuginfo-78.9.0-1.el7_9.ppc64le.rpm SHA-256: 0edf80dcacc02f039d7e37ba3f8bae765f0fdd6c4a3a8171e582e0a78f09654b

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

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