CVE-2025-1933: JIT corruption of WASM i32 return values on 64-bit CPUs

Published Mar 4, 2025
·
Updated

On 64-bit CPUs, when the JIT compiles WASM i32 return values they can pick up bits from left over memory. This can potentially cause them to be treated as a different type. This vulnerability was fixed in Firefox 136, Firefox ESR 115.21, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.

Other sources

On 64-bit CPUs, when the JIT compiles WASM i32 return values they can pick up bits from left over memory. This can potentially cause them to be treated as a different type. This vulnerability affects Firefox < 136, Firefox ESR < 115.21, and Firefox ESR < 128.8.

— Red Hat

Affected Software

26 affected componentsFixes available
Mozilla Firefox<136
Mozilla Firefox ESR<115.21, <128.8
Mozilla Firefox ESR<115.21
115.21
Mozilla Thunderbird<136
136
Mozilla Firefox<115.21.0
Mozilla Firefox<136.0
Mozilla Firefox>=116.0<128.8.0
Mozilla Thunderbird<128.8
Mozilla Thunderbird>=129.0<136.0
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
159.0.1-1
debian/firefox-esr
140.12.0esr-1~deb12u1153.6.0esr-1~deb12u2140.15.0esr-1~deb13u1153.6.0esr-1~deb13u1153.5.1esr-1153.6.0esr-1
debian/thunderbird
1:140.12.0esr-1~deb12u11:153.6.0esr-1~deb12u21:140.12.0esr-1~deb13u11:153.6.0esr-1~deb13u11:153.5.0esr-11:153.6.0esr-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 115.21
  2. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 136
  3. Upgrade

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

    Fixed in 128.8
  4. Upgrade

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

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

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

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

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

    Fixed in 136
  7. Upgrade

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

    Fixed in 159.0.1-1
  8. Upgrade

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

    Fixed in 140.12.0esr-1~deb12u1Fixed in 153.6.0esr-1~deb12u2Fixed in 140.15.0esr-1~deb13u1Fixed in 153.6.0esr-1~deb13u1Fixed in 153.5.1esr-1Fixed in 153.6.0esr-1
  9. Upgrade

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

    Fixed in 1:140.12.0esr-1~deb12u1Fixed in 1:153.6.0esr-1~deb12u2Fixed in 1:140.12.0esr-1~deb13u1Fixed in 1:153.6.0esr-1~deb13u1Fixed in 1:153.5.0esr-1Fixed in 1:153.6.0esr-1
  10. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 136
  11. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 128.8
  12. 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
DescriptionSeverityAffected 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-2025-1933?

CVE-2025-1933 has been rated as important due to the potential for uninitialized memory usage leading to various vulnerabilities.

2

How do I fix CVE-2025-1933?

To remediate CVE-2025-1933, update your Mozilla Firefox to version 136 or later, or Firefox ESR to the appropriate patched versions.

3

What software is affected by CVE-2025-1933?

CVE-2025-1933 affects Mozilla Firefox versions up to 136, Firefox ESR versions up to 115.21 and 128.8, as well as Thunderbird versions up to 136 and 128.8.

4

What exploit scenarios exist for CVE-2025-1933?

CVE-2025-1933 could potentially allow attackers to manipulate i32 return values in WebAssembly, which may lead to unexpected behaviors or application crashes.

5

When was CVE-2025-1933 disclosed?

CVE-2025-1933 was disclosed as part of Mozilla's ongoing security advisories related to its web browser and related software products.

Company

Resources

Contact

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