CVE-2019-17026: Mozilla Firefox And Thunderbird Type Confusion Vulnerability

Published Jan 8, 2020
·
Updated

Incorrect alias information in IonMonkey JIT compiler for setting array elements could lead to a type confusion. We are aware of targeted attacks in the wild abusing this flaw.

Other sources

Mozilla Firefox and Thunderbird contain a type confusion vulnerability due to incorrect alias information in the IonMonkey JIT compiler when setting array elements.

— CISA

Affected Software

16 affected componentsFixes available
redhat/firefox<72.0.1
72.0.1
redhat/firefox<68.4.1
68.4.1
redhat/thunderbird<68.4.1
68.4.1
Mozilla Firefox<72.0.1
Mozilla Firefox ESR<68.4.1
Mozilla Thunderbird<68.4.1
Canonical Ubuntu Linux=16.04
Mozilla Thunderbird<68.4.1
68.4.1
Mozilla Firefox and Thunderbird
Mozilla Firefox<72.0.1
72.0.1
Mozilla Firefox ESR<68.4.1
68.4.1
Mozilla Firefox<68.4.1
Mozilla Firefox<72.0.1
debian/firefox
149.0.2-1
debian/firefox-esr
115.14.0esr-1~deb11u1140.9.1esr-1~deb11u1128.14.0esr-1~deb12u1140.9.1esr-1~deb12u1140.8.0esr-1~deb13u1140.9.1esr-1~deb13u1140.9.1esr-1
debian/thunderbird
1:115.12.0-1~deb11u11:140.9.1esr-1~deb11u11:140.6.0esr-1~deb12u11:140.9.1esr-1~deb12u11:140.8.0esr-1~deb13u11:140.9.1esr-1~deb13u11:140.9.0esr-11:140.9.1esr-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 72.0.1
  2. Upgrade

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

    Fixed in 68.4.1
  3. Upgrade

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

    Fixed in 68.4.1
  4. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 68.4.1
  5. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 72.0.1
  6. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 68.4.1
  7. Upgrade

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

    Fixed in 149.0.2-1
  8. Upgrade

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

    Fixed in 115.14.0esr-1~deb11u1Fixed in 140.9.1esr-1~deb11u1Fixed in 128.14.0esr-1~deb12u1Fixed in 140.9.1esr-1~deb12u1Fixed in 140.8.0esr-1~deb13u1Fixed in 140.9.1esr-1~deb13u1Fixed in 140.9.1esr-1
  9. Upgrade

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

    Fixed in 1:115.12.0-1~deb11u1Fixed in 1:140.9.1esr-1~deb11u1Fixed in 1:140.6.0esr-1~deb12u1Fixed in 1:140.9.1esr-1~deb12u1Fixed in 1:140.8.0esr-1~deb13u1Fixed in 1:140.9.1esr-1~deb13u1Fixed in 1:140.9.0esr-1Fixed in 1:140.9.1esr-1
  10. Upgrade

    Upgrade Mozilla Firefox ESR to a version that resolves this vulnerability.

    Fixed in 68.4.1
  11. Upgrade

    Upgrade Mozilla Thunderbird to a version that resolves this vulnerability.

    Fixed in 68.4.1
  12. Upgrade

    Upgrade Mozilla Firefox to a version that resolves this vulnerability.

    Fixed in 72.0.1
  13. Compensating control

    Given awareness of targeted attacks in the wild abusing this flaw, restrict exposure of affected clients (Firefox/Thunderbird) by limiting access from untrusted networks/users until patched.

Event History

Jan 8, 2020
CVE Published
12:00 AM
Mar 2, 2020
CVE Published
via MITRE·04:05 AM
Data Sourced
via MITRE·04:05 AM
DescriptionWeakness
Data Sourced
via NVD·05:15 AM
DescriptionSeverityWeaknessAffected Software
Nov 3, 2021
Known Exploited
via CISA·12:00 AM
Jan 11, 2024
Data Sourced
via Launchpad·11:22 PM
Description
Feb 20, 2026
Data Sourced
via Ubuntu·10:29 PM
RemedyDescriptionSeverityAffected Software
Apr 14, 2026
Data Sourced
via Debian·11:04 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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Frequently Asked Questions

1

What is the severity of CVE-2019-17026?

The severity of CVE-2019-17026 is critical with a value of 8.8.

2

Which software versions are affected by CVE-2019-17026?

The affected software versions include Firefox ESR < 68.4.1, Thunderbird < 68.4.1, and Firefox < 72.0.1.

3

What is the vulnerability description of CVE-2019-17026?

CVE-2019-17026 is a type confusion vulnerability in the IonMonkey JIT compiler of Mozilla Firefox and Thunderbird, which could be exploited by targeted attacks.

4

How do I fix CVE-2019-17026?

To fix CVE-2019-17026, update to Firefox ESR 68.4.1 or newer, Thunderbird 68.4.1 or newer, or Firefox 72.0.1 or newer.

5

Where can I find more information about CVE-2019-17026?

You can find more information about CVE-2019-17026 in the following references: [Bugzilla](https://bugzilla.mozilla.org/show_bug.cgi?id=1607443), [Mozilla Security Advisories](https://www.mozilla.org/en-US/security/advisories/mfsa2020-03/), [Mozilla Security Advisories](https://www.mozilla.org/security/advisories/mfsa2020-03/).

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