CVE-2019-11759: Buffer Overflow

Published Oct 22, 2019
·
Updated

A flaw was discovered in both Firefox and Thunderbird where 4 bytes of a HMAC output could be written past the end of a buffer stored on the memory stack. This could allow an attacker to execute arbitrary code or lead to a crash. This flaw can be exploited over the network.

Other sources

An attacker could have caused 4 bytes of HMAC output to be written past the end of a buffer stored on the stack. This could be used by an attacker to execute arbitrary code or more likely lead to a crash.

— Mozilla

Affected Software

18 affected componentsFixes available
redhat/firefox<0:68.2.0-4.el6_10
0:68.2.0-4.el6_10
redhat/thunderbird<0:68.2.0-2.el6_10
0:68.2.0-2.el6_10
redhat/firefox<0:68.2.0-1.el7_7
0:68.2.0-1.el7_7
redhat/thunderbird<0:68.2.0-1.el7_7
0:68.2.0-1.el7_7
redhat/firefox<0:68.2.0-2.el8_0
0:68.2.0-2.el8_0
redhat/thunderbird<0:68.2.0-1.el8_0
0:68.2.0-1.el8_0
redhat/firefox<68.2
68.2
redhat/thunderbird<68.2
68.2
Mozilla Firefox<70.0
Mozilla Firefox ESR<68.2
Mozilla Thunderbird<68.2
Canonical Ubuntu Linux=16.04
Mozilla Thunderbird<68.2
68.2
Mozilla Firefox ESR<68.2
68.2
Mozilla Firefox<70
70
debian/firefox
157.0.1-1
debian/firefox-esr
140.12.0esr-1~deb12u1153.5.0esr-1~deb12u1140.15.0esr-1~deb13u1153.5.0esr-1~deb13u1153.4.0esr-1153.5.0esr-1
debian/thunderbird
1:140.12.0esr-1~deb12u11:140.17.0esr-1~deb12u11:140.12.0esr-1~deb13u11:140.17.0esr-1~deb13u11:153.4.0esr-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/firefox to a version that resolves this vulnerability.

    Fixed in 0:68.2.0-4.el6_10
  2. Upgrade

    Upgrade redhat/thunderbird to a version that resolves this vulnerability.

    Fixed in 0:68.2.0-2.el6_10
  3. Upgrade

    Upgrade redhat/firefox to a version that resolves this vulnerability.

    Fixed in 0:68.2.0-1.el7_7
  4. Upgrade

    Upgrade redhat/thunderbird to a version that resolves this vulnerability.

    Fixed in 0:68.2.0-1.el7_7
  5. Upgrade

    Upgrade redhat/firefox to a version that resolves this vulnerability.

    Fixed in 0:68.2.0-2.el8_0
  6. Upgrade

    Upgrade redhat/thunderbird to a version that resolves this vulnerability.

    Fixed in 0:68.2.0-1.el8_0
  7. Upgrade

    Upgrade redhat/firefox to a version that resolves this vulnerability.

    Fixed in 68.2
  8. Upgrade

    Upgrade redhat/thunderbird to a version that resolves this vulnerability.

    Fixed in 68.2
  9. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 68.2
  10. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 68.2
  11. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 70
  12. Upgrade

    Upgrade debian/firefox to a version that resolves this vulnerability.

    Fixed in 157.0.1-1
  13. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 140.12.0esr-1~deb12u1Fixed in 153.5.0esr-1~deb12u1Fixed in 140.15.0esr-1~deb13u1Fixed in 153.5.0esr-1~deb13u1Fixed in 153.4.0esr-1Fixed in 153.5.0esr-1
  14. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:140.12.0esr-1~deb12u1Fixed in 1:140.17.0esr-1~deb12u1Fixed in 1:140.12.0esr-1~deb13u1Fixed in 1:140.17.0esr-1~deb13u1Fixed in 1:153.4.0esr-1

Event History

Oct 22, 2019
CVE Published
12:00 AM
Jan 8, 2020
CVE Published
via MITRE·07:48 PM
Data Sourced
via MITRE·07:48 PM
DescriptionWeakness
Data Sourced
via NVD·08:15 PM
DescriptionSeverityWeaknessAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:14 PM
Description
Feb 20, 2026
Data Sourced
via Ubuntu·08:34 PM
RemedyDescriptionSeverityAffected Software
Oct 15, 2026
Data Sourced
via Debian·07:01 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What is CVE-2019-11759?

CVE-2019-11759 is a vulnerability that could allow an attacker to execute arbitrary code or cause a crash by writing 4 bytes of HMAC output past the end of a buffer stored on the stack.

2

Which software versions are affected by CVE-2019-11759?

Firefox versions earlier than 70, Thunderbird versions earlier than 68.2, and Firefox ESR versions earlier than 68.2 are affected by CVE-2019-11759.

3

What is the severity of CVE-2019-11759?

CVE-2019-11759 has a high severity rating of 8.8.

4

How can this vulnerability be fixed?

To fix CVE-2019-11759, update Firefox to version 70 or later, Thunderbird to version 68.2 or later, and Firefox ESR to version 68.2 or later.

5

Where can I find more information about CVE-2019-11759?

More information about CVE-2019-11759 can be found in the following references: [Mozilla Bugzilla](https://bugzilla.mozilla.org/show_bug.cgi?id=1577953), [Mozilla Security Advisory](https://www.mozilla.org/en-US/security/advisories/mfsa2019-33/), [Mozilla Security Advisory](https://www.mozilla.org/en-US/security/advisories/mfsa2019-35/).

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