CVE-2019-9793: Buffer Overflow

Published Mar 19, 2019
·
Updated

A mechanism was discovered that removes some bounds checking for string, array, or typed array accesses if Spectre mitigations have been disabled. This vulnerability could allow an attacker to create an arbitrary value in compiled JavaScript, for which the range analysis will infer a fully controlled, incorrect range in circumstances where users have explicitly disabled Spectre mitigations.

Note: Spectre mitigations are currently enabled for all users by default settings.

External Reference:

https://www.mozilla.org/en-US/security/advisories/mfsa2019-08/#CVE-2019-9793

Other sources

A mechanism was discovered that removes some bounds checking for string, array, or typed array accesses if Spectre mitigations have been disabled. This vulnerability could allow an attacker to create an arbitrary value in compiled JavaScript, for which the range analysis will infer a fully controlled, incorrect range in circumstances where users have explicitly disabled Spectre mitigations. Note: Spectre mitigations are currently enabled for all users by default settings.

A mechanism was discovered that removes some bounds checking for string, array, or typed array accesses if Spectre mitigations have been disabled. This vulnerability could allow an attacker to create an arbitrary value in compiled JavaScript, for which the range analysis will infer a fully controlled, incorrect range in circumstances where users have explicitly disabled Spectre mitigations. Note: Spectre mitigations are currently enabled for all users by default settings.. This vulnerability affects Thunderbird < 60.6, Firefox ESR < 60.6, and Firefox < 66.

— Launchpad

Affected Software

9 affected componentsFixes available
Mozilla Firefox<66
66
Mozilla Thunderbird<60.6
60.6
Mozilla Firefox<66.0
Mozilla Firefox ESR<60.6
Mozilla Thunderbird<60.6
Mozilla Firefox ESR<60.6
60.6
debian/firefox
152.0.1-1
debian/firefox-esr
115.14.0esr-1~deb11u1140.12.0esr-1~deb11u1140.10.2esr-1~deb12u1140.12.0esr-1~deb12u1140.10.2esr-1~deb13u1140.12.0esr-1~deb13u1140.11.0esr-1140.12.0esr-1
debian/thunderbird
1:115.12.0-1~deb11u11:140.12.0esr-1~deb11u11:140.10.1esr-1~deb12u11:140.12.0esr-1~deb12u11:140.10.1esr-1~deb13u11:140.12.0esr-1~deb13u11:140.11.0esr-11:140.12.0esr-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 66
  2. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 60.6
  3. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 60.6
  4. Upgrade

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

    Fixed in 152.0.1-1
  5. Upgrade

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

    Fixed in 115.14.0esr-1~deb11u1Fixed in 140.12.0esr-1~deb11u1Fixed in 140.10.2esr-1~deb12u1Fixed in 140.12.0esr-1~deb12u1Fixed in 140.10.2esr-1~deb13u1Fixed in 140.12.0esr-1~deb13u1Fixed in 140.11.0esr-1Fixed in 140.12.0esr-1
  6. Upgrade

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

    Fixed in 1:115.12.0-1~deb11u1Fixed in 1:140.12.0esr-1~deb11u1Fixed in 1:140.10.1esr-1~deb12u1Fixed in 1:140.12.0esr-1~deb12u1Fixed in 1:140.10.1esr-1~deb13u1Fixed in 1:140.12.0esr-1~deb13u1Fixed in 1:140.11.0esr-1Fixed in 1:140.12.0esr-1
  7. Upgrade

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

    Fixed in 115.14.0esr-1~deb11u1
  8. Upgrade

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

    Fixed in 140.12.0esr-1~deb11u1
  9. Upgrade

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

    Fixed in 140.10.2esr-1~deb12u1
  10. Upgrade

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

    Fixed in 140.12.0esr-1~deb12u1
  11. Upgrade

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

    Fixed in 140.10.2esr-1~deb13u1
  12. Upgrade

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

    Fixed in 140.12.0esr-1~deb13u1
  13. Upgrade

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

    Fixed in 140.11.0esr-1
  14. Upgrade

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

    Fixed in 140.12.0esr-1
  15. Upgrade

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

    Fixed in 1:115.12.0-1~deb11u1
  16. Upgrade

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

    Fixed in 1:140.12.0esr-1~deb11u1
  17. Upgrade

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

    Fixed in 1:140.10.1esr-1~deb12u1
  18. Upgrade

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

    Fixed in 1:140.12.0esr-1~deb12u1
  19. Upgrade

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

    Fixed in 1:140.10.1esr-1~deb13u1
  20. Upgrade

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

    Fixed in 1:140.12.0esr-1~deb13u1
  21. Upgrade

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

    Fixed in 1:140.11.0esr-1
  22. Upgrade

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

    Fixed in 1:140.12.0esr-1
  23. Configuration

    Ensure Spectre mitigations are enabled (do not disable Spectre mitigations in browser settings or via startup flags) so that the out-of-bounds removal described is not exposed.

    Firefox / Firefox ESR / Thunderbird Spectre mitigations = enabled

Event History

Mar 19, 2019
CVE Published
12:00 AM
Mar 20, 2019
Data Sourced
via Red Hat·02:14 AM
DescriptionSeverityAffected Software
Apr 26, 2019
CVE Published
via MITRE·04:13 PM
Data Sourced
via MITRE·04:13 PM
DescriptionWeakness
Data Sourced
via NVD·05:29 PM
DescriptionSeverityWeaknessAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:33 PM
Description
Feb 19, 2026
Data Sourced
via Ubuntu·05:59 PM
RemedyDescriptionSeverityAffected Software
Jun 20, 2026
Data Sourced
via Debian·04:03 AM
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 CVE-2019-9793?

CVE-2019-9793 is a vulnerability that removes some bounds checking for string, array, or typed array accesses in JavaScript if Spectre mitigations have been disabled.

2

What is the severity of CVE-2019-9793?

CVE-2019-9793 has a severity rating of high.

3

How does CVE-2019-9793 affect Firefox?

CVE-2019-9793 affects Mozilla Firefox versions up to and excluding 66.0.

4

How does CVE-2019-9793 affect Firefox ESR?

CVE-2019-9793 affects Mozilla Firefox ESR versions up to and excluding 60.6.

5

How can I fix CVE-2019-9793 in Firefox?

To fix CVE-2019-9793 in Firefox, update to version 66.0 or later.

6

How can I fix CVE-2019-9793 in Firefox ESR?

To fix CVE-2019-9793 in Firefox ESR, update to version 60.6 or later.

Company

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