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NVD / CVE Program· CNA mozilla

CVE-2024-7520: A type confusion bug in WebAssembly could be leveraged by an attacker to potentially achieve code execution.

Noroxi assessment

Priority: Monitor (action score 35/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.63% (FIRST EPSS); higher than 50.2% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. A user must open a link or visit a page. No special conditions are required; it is repeatable.
  • Fixed version: firefox (AlmaLinux:8) 115.14.0-2.el8_10.alma.1; thunderbird (AlmaLinux:8) 115.14.0-1.el8_10.alma.1; firefox (AlmaLinux:9) 115.14.0-2.el9_4.alma.1.

Low priority for now. Upgrade to firefox (AlmaLinux:8) 115.14.0-2.el8_10.alma.1; thunderbird (AlmaLinux:8) 115.14.0-1.el8_10.alma.1; firefox (AlmaLinux:9) 115.14.0-2.el9_4.alma.1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

A type confusion bug in WebAssembly could be leveraged by an attacker to potentially achieve code execution. This vulnerability affects Firefox < 129, Firefox ESR < 128.1, and Thunderbird < 128.1.

HighCVSS 8.8 · v3.1—No exploit Fix available
Published
Aug 6, 2024
Updated
Jun 17, 2026
EPSS
0.6% · 50th percentile

Report tools

JSON

Action score

35

Monitor

Low priority for now.

CVSS
35 / 40 · 8.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.6%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2024-7520

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
mozillafirefox
mozillafirefox esr
mozillathunderbird

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • mozilla firefoxbefore 129.0
  • mozilla firefox esrbefore 128.1.0
  • mozilla thunderbirdbefore 128.1.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (mozilla). Independent of NVD's CPE analysis and usually ahead of it.

  • Mozilla Firefox

    • unspecified and later · before 129affected

  • Mozilla Firefox ESR

    • unspecified and later · before 128.1affected

  • Mozilla Thunderbird

    • unspecified and later · before 128.1affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
AlmaLinux:8firefoxbefore 115.14.0-2.el8_10.alma.1115.14.0-2.el8_10.alma.1
AlmaLinux:8thunderbirdbefore 115.14.0-1.el8_10.alma.1115.14.0-1.el8_10.alma.1
AlmaLinux:9firefoxbefore 115.14.0-2.el9_4.alma.1115.14.0-2.el9_4.alma.1
AlmaLinux:9firefox-x11before 115.14.0-2.el9_4.alma.1115.14.0-2.el9_4.alma.1
AlmaLinux:9thunderbirdbefore 115.14.0-1.el9_4.alma.1115.14.0-1.el9_4.alma.1
openSUSE:Leap 15.5MozillaFirefoxbefore 128.1.0-150200.152.146.1128.1.0-150200.152.146.1
openSUSE:Leap 15.5MozillaFirefox-branding-SLEbefore 128-150200.9.16.1128-150200.9.16.1
openSUSE:Leap 15.5MozillaThunderbirdbefore 128.2.3-150200.8.177.1128.2.3-150200.8.177.1
openSUSE:TumbleweedMozillaFirefoxbefore 129.0-1.1129.0-1.1
Red Hat:enterprise_linux:8::appstreamfirefoxbefore 0:115.14.0-2.el8_100:115.14.0-2.el8_10
Red Hat:enterprise_linux:8::appstreamfirefox-debuginfobefore 0:115.14.0-2.el8_100:115.14.0-2.el8_10
Red Hat:enterprise_linux:8::appstreamfirefox-debugsourcebefore 0:115.14.0-2.el8_100:115.14.0-2.el8_10
Red Hat:enterprise_linux:8::appstreamthunderbirdbefore 0:115.14.0-1.el8_100:115.14.0-1.el8_10
Red Hat:enterprise_linux:8::appstreamthunderbird-debuginfobefore 0:115.14.0-1.el8_100:115.14.0-1.el8_10
Red Hat:enterprise_linux:8::appstreamthunderbird-debugsourcebefore 0:115.14.0-1.el8_100:115.14.0-1.el8_10
Red Hat:enterprise_linux:9::appstreamfirefoxbefore 0:115.14.0-2.el9_40:115.14.0-2.el9_4
Red Hat:enterprise_linux:9::appstreamfirefox-debuginfobefore 0:115.14.0-2.el9_40:115.14.0-2.el9_4
Red Hat:enterprise_linux:9::appstreamfirefox-debugsourcebefore 0:115.14.0-2.el9_40:115.14.0-2.el9_4
Red Hat:enterprise_linux:9::appstreamfirefox-x11before 0:115.14.0-2.el9_40:115.14.0-2.el9_4
Red Hat:enterprise_linux:9::appstreamthunderbirdbefore 0:115.14.0-1.el9_40:115.14.0-1.el9_4
Red Hat:enterprise_linux:9::appstreamthunderbird-debuginfobefore 0:115.14.0-1.el9_40:115.14.0-1.el9_4
Red Hat:enterprise_linux:9::appstreamthunderbird-debugsourcebefore 0:115.14.0-1.el9_40:115.14.0-1.el9_4
Red Hat:rhel_aus:8.2::appstreamfirefoxbefore 0:115.14.0-2.el8_20:115.14.0-2.el8_2
Red Hat:rhel_aus:8.2::appstreamfirefox-debuginfobefore 0:115.14.0-2.el8_20:115.14.0-2.el8_2

+44

Same product

mozilla: all records

Other highest-scoring records for the same primary product.

  • CVE-2010-3765Mozilla Firefox 3.5.x through 3.5.14 and 3.6.x through 3.6.11, Thunderbird 3.1.6 before 3.1.6 and 3.0.x before 3.0.10, and SeaMonkey 2.x befKEV
    94Now
  • CVE-2019-11708Insufficient vetting of parameters passed with the Prompt:Open IPC message between child and parent processes can result in the non-sandboxeKEV
    87Now
  • CVE-2015-4495The PDF reader in Mozilla Firefox before 39.0.3, Firefox ESR 38.x before 38.1.1, and Firefox OS before 2.2 allows remote attackers to bypassKEV
    86Now

Published before and after this one in the same product

  • ← EarlierCVE-2024-7518Aug 6, 2024 · Select options could obscure the fullscreen notification dialog.
    26Monitor
  • ← EarlierCVE-2024-7519Aug 6, 2024 · Insufficient checks when processing graphics shared memory could have led to memory corruption.
    38Monitor
  • Later →CVE-2024-7521Aug 6, 2024 · Incomplete WebAssembly exception handing could have led to a use-after-free.
    35Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
almalinux:firefox115.14.0-2.el9_4.alma.1 · AlmaLinux:9Package registry (OSV)
almalinux:firefox-x11115.14.0-2.el9_4.alma.1 · AlmaLinux:9Package registry (OSV)
almalinux:thunderbird115.14.0-1.el9_4.alma.1 · AlmaLinux:9Package registry (OSV)
opensuse:MozillaFirefox128.1.0-150200.152.146.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:MozillaFirefox-branding-SLE128-150200.9.16.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:MozillaThunderbird128.2.3-150200.8.177.1 · openSUSE:Leap 15.5Package registry (OSV)
red hat:firefox0:115.14.0-2.el9_4 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:firefox-debuginfo0:115.14.0-2.el9_4 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:firefox-debugsource0:115.14.0-2.el9_4 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:firefox-x110:115.14.0-2.el9_4 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:thunderbird0:115.14.0-1.el9_4 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:thunderbird-debuginfo0:115.14.0-1.el9_4 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:thunderbird-debugsource0:115.14.0-1.el9_4 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
rocky linux:firefox0:115.14.0-2.el8_10 · Rocky Linux:8Package registry (OSV)
rocky linux:thunderbird0:115.14.0-1.el8_10 · Rocky Linux:8Package registry (OSV)
suse:MozillaFirefox128.1.0-112.221.1 · SUSE:Linux Enterprise Software Development Kit 12 SP5Package registry (OSV)
suse:MozillaFirefox128.1.0-150200.152.146.1 · SUSE:Linux Enterprise Module for Desktop Applications 15 SP5Package registry (OSV)
suse:MozillaFirefox-branding-SLE128-150200.9.16.1 · SUSE:Linux Enterprise Module for Desktop Applications 15 SP5Package registry (OSV)
suse:MozillaFirefox-branding-SLE128-35.15.1 · SUSE:Linux Enterprise Server 12 SP5Package registry (OSV)
suse:MozillaThunderbird128.2.3-150200.8.177.1 · SUSE:Linux Enterprise Module for Package Hub 15 SP5Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2024-838128 days apartA potentially exploitable type confusion could be triggered when looking up a property name on an object being used as the `with` environmen
    40Plan
  • CVE-2024-838528 days apartA difference in the handling of StructFields and ArrayTypes in WASM could be used to trigger an exploitable type confusion vulnerability.
    39Monitor
  • CVE-2025-14325490 days apartJIT miscompilation in the JavaScript Engine: JIT component
    29Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • A user must open a link or visit a page.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
Required
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-843 · Access of Resource Using Incompatible Type ('Type Confusion')

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (3 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records