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Red Hat Product Errata RHSA-2021:4607 - Security Advisory
Issued:
2021-11-10
Updated:
2021-11-10

RHSA-2021:4607 - 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 8.1 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 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 for x86_64 - Extended Update Support 8.1 x86_64
  • Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 8.1 s390x
  • Red Hat Enterprise Linux for Power, little endian - Extended Update Support 8.1 ppc64le
  • Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.1 aarch64
  • Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.1 ppc64le
  • Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.1 x86_64

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 for x86_64 - Extended Update Support 8.1

SRPM
firefox-91.3.0-1.el8_1.src.rpm SHA-256: b18ca006b58d247f0acace890301d80199a11a8faef7b312f4e51ca1a525b1ab
x86_64
firefox-91.3.0-1.el8_1.x86_64.rpm SHA-256: a957b96dadb5a2305d09246a7c6870ea5c6ab7e9f3f249e9824db2573963ceb0
firefox-debuginfo-91.3.0-1.el8_1.x86_64.rpm SHA-256: 9a64acab157af61a8f1449fcc272aecfd300e3b0b95bfab8eef52a1df5a3b2b0
firefox-debugsource-91.3.0-1.el8_1.x86_64.rpm SHA-256: eaeb40a5aee8426723b04b3307a0318d582fb5bc792d0ce216667b12e59f721b

Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 8.1

SRPM
firefox-91.3.0-1.el8_1.src.rpm SHA-256: b18ca006b58d247f0acace890301d80199a11a8faef7b312f4e51ca1a525b1ab
s390x
firefox-91.3.0-1.el8_1.s390x.rpm SHA-256: 4e1ad0d3eb7755b5297b33eaf1021049a023bc0fc86b82b190fe1238a6ea4a11
firefox-debuginfo-91.3.0-1.el8_1.s390x.rpm SHA-256: a575f4c69bc85255bbae1602c6784f8aea3465f3c99da8b70331584c0d79298d
firefox-debugsource-91.3.0-1.el8_1.s390x.rpm SHA-256: e4559a936af3e0b3bcb0e0adf132856bcf3be639a34ed751bec47efa3e69c5a2

Red Hat Enterprise Linux for Power, little endian - Extended Update Support 8.1

SRPM
firefox-91.3.0-1.el8_1.src.rpm SHA-256: b18ca006b58d247f0acace890301d80199a11a8faef7b312f4e51ca1a525b1ab
ppc64le
firefox-91.3.0-1.el8_1.ppc64le.rpm SHA-256: 6ecac736d43bb72e8921743e1d70781a66d9cff782411253c976485e3e42c8fb
firefox-debuginfo-91.3.0-1.el8_1.ppc64le.rpm SHA-256: a1ae8def82bb6b26144b0d958e7b73b929fe194abdd9d422cdecf5018a2de827
firefox-debugsource-91.3.0-1.el8_1.ppc64le.rpm SHA-256: cbc823c3878f9473417c0373b48706e2a70e0690ff58bc1e99b4bde6d1e83f9b

Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.1

SRPM
firefox-91.3.0-1.el8_1.src.rpm SHA-256: b18ca006b58d247f0acace890301d80199a11a8faef7b312f4e51ca1a525b1ab
aarch64
firefox-91.3.0-1.el8_1.aarch64.rpm SHA-256: 3a6c5c394463a885b9089bbc95e38201560db4adc389dee18fb9ebfca3e82f8b
firefox-debuginfo-91.3.0-1.el8_1.aarch64.rpm SHA-256: 40a61bf021d8e3339a1699f2278d449b1912b7ed682a5eea6c6a03491911b0af
firefox-debugsource-91.3.0-1.el8_1.aarch64.rpm SHA-256: e25bcd15b5d24f54abe54317e1acdc80cbcaf5aac9ef49ca8c70e447f55c49dd

Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.1

SRPM
firefox-91.3.0-1.el8_1.src.rpm SHA-256: b18ca006b58d247f0acace890301d80199a11a8faef7b312f4e51ca1a525b1ab
ppc64le
firefox-91.3.0-1.el8_1.ppc64le.rpm SHA-256: 6ecac736d43bb72e8921743e1d70781a66d9cff782411253c976485e3e42c8fb
firefox-debuginfo-91.3.0-1.el8_1.ppc64le.rpm SHA-256: a1ae8def82bb6b26144b0d958e7b73b929fe194abdd9d422cdecf5018a2de827
firefox-debugsource-91.3.0-1.el8_1.ppc64le.rpm SHA-256: cbc823c3878f9473417c0373b48706e2a70e0690ff58bc1e99b4bde6d1e83f9b

Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.1

SRPM
firefox-91.3.0-1.el8_1.src.rpm SHA-256: b18ca006b58d247f0acace890301d80199a11a8faef7b312f4e51ca1a525b1ab
x86_64
firefox-91.3.0-1.el8_1.x86_64.rpm SHA-256: a957b96dadb5a2305d09246a7c6870ea5c6ab7e9f3f249e9824db2573963ceb0
firefox-debuginfo-91.3.0-1.el8_1.x86_64.rpm SHA-256: 9a64acab157af61a8f1449fcc272aecfd300e3b0b95bfab8eef52a1df5a3b2b0
firefox-debugsource-91.3.0-1.el8_1.x86_64.rpm SHA-256: eaeb40a5aee8426723b04b3307a0318d582fb5bc792d0ce216667b12e59f721b

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

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