CVE-2025-1938: Memory safety bugs fixed in Firefox 136, Thunderbird 136, Firefox ESR 128.8, and Thunderbird 128.8

Published Mar 4, 2025
·
Updated

Memory safety bugs present in Firefox 135, Thunderbird 135, Firefox ESR 128.7, and Thunderbird 128.7. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 136, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.

Other sources

Memory safety bugs present in Firefox 135, Thunderbird 135, Firefox ESR 128.7, and Thunderbird 128.7. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 136 and Firefox ESR < 128.8.

— Red Hat

Affected Software

25 affected componentsFixes available
Mozilla Firefox<136
Mozilla Firefox ESR<128.8
Mozilla Thunderbird
Mozilla Thunderbird<136
136
Mozilla Firefox<128.7.0
Mozilla Firefox<135.0
Mozilla Thunderbird<128.7.0
Mozilla Thunderbird>=129.0<135.0
Mozilla Thunderbird<128.8
128.8
ubuntu/mozjs52*
ubuntu/mozjs38*
ubuntu/firefox<136.0+build3-0ubuntu0.20.04.1
136.0+build3-0ubuntu0.20.04.1
ubuntu/mozjs68*
ubuntu/mozjs52*
ubuntu/mozjs102*
ubuntu/mozjs78*
ubuntu/mozjs91*
ubuntu/thunderbird<1:128.12.0+build1-0ubuntu0.22.04.1
1:128.12.0+build1-0ubuntu0.22.04.1
ubuntu/mozjs102*
ubuntu/mozjs115*
Mozilla Firefox ESR<128.8
128.8
Mozilla Firefox<136
136
debian/firefox
160.0-1
debian/firefox-esr
140.12.0esr-1~deb12u1153.7.0esr-1~deb12u1140.15.0esr-1~deb13u1153.7.0esr-1~deb13u1153.5.1esr-1153.7.0esr-1
debian/thunderbird
1:140.12.0esr-1~deb12u11:153.7.0esr-1~deb12u11:140.12.0esr-1~deb13u11:153.7.0esr-1~deb13u11:153.5.0esr-11:153.7.0esr-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 136
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 128.8
  3. Upgrade

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

    Fixed in 136.0+build3-0ubuntu0.20.04.1
  4. Upgrade

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

    Fixed in 1:128.12.0+build1-0ubuntu0.22.04.1
  5. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 136
  6. Upgrade

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

    Fixed in 160.0-1
  7. Upgrade

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

    Fixed in 140.12.0esr-1~deb12u1Fixed in 153.7.0esr-1~deb12u1Fixed in 140.15.0esr-1~deb13u1Fixed in 153.7.0esr-1~deb13u1Fixed in 153.5.1esr-1Fixed in 153.7.0esr-1
  8. Upgrade

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

    Fixed in 1:140.12.0esr-1~deb12u1Fixed in 1:153.7.0esr-1~deb12u1Fixed in 1:140.12.0esr-1~deb13u1Fixed in 1:153.7.0esr-1~deb13u1Fixed in 1:153.5.0esr-1Fixed in 1:153.7.0esr-1
  9. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 136
  10. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 128.8
  11. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 128.8

Event History

Mar 4, 2025
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
Data Sourced
via Ubuntu·12:00 AM
RemedyDescriptionSeverityAffected Software
CVE Published
via MITRE·01:31 PM
Data Sourced
via MITRE·01:31 PM
Description
Data Sourced
via Red Hat·02:01 PM
DescriptionSeverityAffected Software
Data Sourced
via OSV·02:15 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·02:15 PM
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What is the severity of CVE-2025-1938?

CVE-2025-1938 has a high severity rating due to the potential for memory corruption that could allow arbitrary code execution.

2

How do I fix CVE-2025-1938?

To fix CVE-2025-1938, update Mozilla Firefox to version 136 or Thunderbird to the latest version available.

3

What software is affected by CVE-2025-1938?

CVE-2025-1938 affects Firefox versions up to 135, Thunderbird versions up to 135, and Firefox ESR versions up to 128.7.

4

Can CVE-2025-1938 be exploited?

There is a possibility that CVE-2025-1938 could be exploited to run arbitrary code if attackers leverage the memory safety bugs.

5

What should I do if I cannot update to a new version for CVE-2025-1938?

If you cannot update, consider using alternative browsers until a fix is applied or apply additional security measures to reduce risk.

Company

Resources

Contact

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