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Red Hat Product Errata RHSA-2021:4116 - Security Advisory
Issued:
2021-11-03
Updated:
2021-11-03

RHSA-2021:4116 - Security Advisory

  • Overview
  • Updated Packages

Synopsis

Important: firefox 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 firefox is now available for Red Hat Enterprise Linux 7.

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 Firefox is an open-source web browser, designed for standards compliance, performance, and portability.

This update upgrades Firefox to version 91.3.0 ESR.

Security Fix(es):

  • Mozilla: Use-after-free in HTTP2 Session object
  • Mozilla: Memory safety bugs fixed in Firefox 94 and Firefox ESR 91.3
  • Mozilla: iframe sandbox rules did not apply to XSLT stylesheets (CVE-2021-38503)
  • Mozilla: Use-after-free in file picker dialog (CVE-2021-38504)
  • Mozilla: Firefox could be coaxed into going into fullscreen mode without notification or warning (CVE-2021-38506)
  • Mozilla: Opportunistic Encryption in HTTP2 could be used to bypass the Same-Origin-Policy on services hosted on other ports (CVE-2021-38507)
  • Mozilla: Permission Prompt could be overlaid, resulting in user confusion and potential spoofing (CVE-2021-38508)
  • Mozilla: Javascript alert box could have been spoofed onto an arbitrary domain (CVE-2021-38509)

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 - 2019621 - CVE-2021-38503 Mozilla: iframe sandbox rules did not apply to XSLT stylesheets
  • BZ - 2019622 - CVE-2021-38504 Mozilla: Use-after-free in file picker dialog
  • BZ - 2019624 - CVE-2021-38506 Mozilla: Firefox could be coaxed into going into fullscreen mode without notification or warning
  • BZ - 2019625 - CVE-2021-38507 Mozilla: Opportunistic Encryption in HTTP2 could be used to bypass the Same-Origin-Policy on services hosted on other ports
  • BZ - 2019626 - Mozilla: Use-after-free in HTTP2 Session object
  • BZ - 2019627 - CVE-2021-38508 Mozilla: Permission Prompt could be overlaid, resulting in user confusion and potential spoofing
  • BZ - 2019628 - CVE-2021-38509 Mozilla: Javascript alert box could have been spoofed onto an arbitrary domain
  • BZ - 2019630 - Mozilla: Memory safety bugs fixed in Firefox 94 and Firefox ESR 91.3

CVEs

  • CVE-2021-38503
  • CVE-2021-38504
  • CVE-2021-38506
  • CVE-2021-38507
  • CVE-2021-38508
  • CVE-2021-38509
  • CVE-2021-43534
  • CVE-2021-43535

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-91.3.0-1.el7_9.src.rpm SHA-256: 218020604471dbc182d86010565233fdaa02b1f7905f5c46f99d241d47296686
x86_64
firefox-91.3.0-1.el7_9.i686.rpm SHA-256: 388478cc28409fb41adc953508179ecdd1c31b3ad01437de30f8f9a574b80252
firefox-91.3.0-1.el7_9.x86_64.rpm SHA-256: 2d41873f37ce53e43e6e60af80d53a3fd5955b923788f3f3f342ba9026d975ef
firefox-debuginfo-91.3.0-1.el7_9.x86_64.rpm SHA-256: 76a78d9efa9c84522d190e0561c43becee7ad091ac147fa088fd4ef82d7b2e32

Red Hat Enterprise Linux Server - Extended Life Cycle Support 7

SRPM
firefox-91.3.0-1.el7_9.src.rpm SHA-256: 218020604471dbc182d86010565233fdaa02b1f7905f5c46f99d241d47296686
x86_64
firefox-91.3.0-1.el7_9.i686.rpm SHA-256: 388478cc28409fb41adc953508179ecdd1c31b3ad01437de30f8f9a574b80252
firefox-91.3.0-1.el7_9.x86_64.rpm SHA-256: 2d41873f37ce53e43e6e60af80d53a3fd5955b923788f3f3f342ba9026d975ef
firefox-debuginfo-91.3.0-1.el7_9.x86_64.rpm SHA-256: 76a78d9efa9c84522d190e0561c43becee7ad091ac147fa088fd4ef82d7b2e32

Red Hat Enterprise Linux Workstation 7

SRPM
firefox-91.3.0-1.el7_9.src.rpm SHA-256: 218020604471dbc182d86010565233fdaa02b1f7905f5c46f99d241d47296686
x86_64
firefox-91.3.0-1.el7_9.i686.rpm SHA-256: 388478cc28409fb41adc953508179ecdd1c31b3ad01437de30f8f9a574b80252
firefox-91.3.0-1.el7_9.x86_64.rpm SHA-256: 2d41873f37ce53e43e6e60af80d53a3fd5955b923788f3f3f342ba9026d975ef
firefox-debuginfo-91.3.0-1.el7_9.x86_64.rpm SHA-256: 76a78d9efa9c84522d190e0561c43becee7ad091ac147fa088fd4ef82d7b2e32

Red Hat Enterprise Linux Desktop 7

SRPM
firefox-91.3.0-1.el7_9.src.rpm SHA-256: 218020604471dbc182d86010565233fdaa02b1f7905f5c46f99d241d47296686
x86_64
firefox-91.3.0-1.el7_9.i686.rpm SHA-256: 388478cc28409fb41adc953508179ecdd1c31b3ad01437de30f8f9a574b80252
firefox-91.3.0-1.el7_9.x86_64.rpm SHA-256: 2d41873f37ce53e43e6e60af80d53a3fd5955b923788f3f3f342ba9026d975ef
firefox-debuginfo-91.3.0-1.el7_9.x86_64.rpm SHA-256: 76a78d9efa9c84522d190e0561c43becee7ad091ac147fa088fd4ef82d7b2e32

Red Hat Enterprise Linux for IBM z Systems 7

SRPM
firefox-91.3.0-1.el7_9.src.rpm SHA-256: 218020604471dbc182d86010565233fdaa02b1f7905f5c46f99d241d47296686
s390x
firefox-91.3.0-1.el7_9.s390x.rpm SHA-256: 56c2cc7ac13f30856991c32e4bdf01b37ad35bc7b36e707f5dd0fc5db177a777
firefox-debuginfo-91.3.0-1.el7_9.s390x.rpm SHA-256: 3cbbdc390d24712a63fef8292b3556359a006fd96a6ab1be2754c86d22c50d44

Red Hat Enterprise Linux for Power, big endian 7

SRPM
firefox-91.3.0-1.el7_9.src.rpm SHA-256: 218020604471dbc182d86010565233fdaa02b1f7905f5c46f99d241d47296686
ppc64
firefox-91.3.0-1.el7_9.ppc64.rpm SHA-256: b3f57ca733f753890555421bf85804a0f7b62220e3aa186b04205bfb02f05e15
firefox-debuginfo-91.3.0-1.el7_9.ppc64.rpm SHA-256: 76608e43132287a4285c7acf355e07002265f631c322cbbdebc42fb866b49654

Red Hat Enterprise Linux for Power, little endian 7

SRPM
firefox-91.3.0-1.el7_9.src.rpm SHA-256: 218020604471dbc182d86010565233fdaa02b1f7905f5c46f99d241d47296686
ppc64le
firefox-91.3.0-1.el7_9.ppc64le.rpm SHA-256: 8d13b716bdfa24134f618b68eef6b8308dde23155061e0ffbcd1ced367b9aebb
firefox-debuginfo-91.3.0-1.el7_9.ppc64le.rpm SHA-256: 8aba50e97a4d296aae412f28935de55ec609a2349b441f67792842bb58cb1e98

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

SRPM
firefox-91.3.0-1.el7_9.src.rpm SHA-256: 218020604471dbc182d86010565233fdaa02b1f7905f5c46f99d241d47296686
s390x
firefox-91.3.0-1.el7_9.s390x.rpm SHA-256: 56c2cc7ac13f30856991c32e4bdf01b37ad35bc7b36e707f5dd0fc5db177a777
firefox-debuginfo-91.3.0-1.el7_9.s390x.rpm SHA-256: 3cbbdc390d24712a63fef8292b3556359a006fd96a6ab1be2754c86d22c50d44

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

SRPM
firefox-91.3.0-1.el7_9.src.rpm SHA-256: 218020604471dbc182d86010565233fdaa02b1f7905f5c46f99d241d47296686
ppc64
firefox-91.3.0-1.el7_9.ppc64.rpm SHA-256: b3f57ca733f753890555421bf85804a0f7b62220e3aa186b04205bfb02f05e15
firefox-debuginfo-91.3.0-1.el7_9.ppc64.rpm SHA-256: 76608e43132287a4285c7acf355e07002265f631c322cbbdebc42fb866b49654

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

SRPM
firefox-91.3.0-1.el7_9.src.rpm SHA-256: 218020604471dbc182d86010565233fdaa02b1f7905f5c46f99d241d47296686
ppc64le
firefox-91.3.0-1.el7_9.ppc64le.rpm SHA-256: 8d13b716bdfa24134f618b68eef6b8308dde23155061e0ffbcd1ced367b9aebb
firefox-debuginfo-91.3.0-1.el7_9.ppc64le.rpm SHA-256: 8aba50e97a4d296aae412f28935de55ec609a2349b441f67792842bb58cb1e98

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

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