dbcve.org
FirefoxWeb browser · Mozilla

CVE-2024-8381

CRITICAL · 9.8 CVSS v3.1 Published 2024-09-03
Fix available
A fix is available. Upgrade to 115.15 / 128.2 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A potentially exploitable type confusion could be triggered when looking up a property name on an object being used as the `with` environment. This vulnerability affects Firefox < 130, Firefox ESR < 128.2, Firefox ESR < 115.15, Thunderbird < 128.2, and Thunderbird < 115.15.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Type confusion vulnerability in Mozilla's SpiderMonkey JavaScript engine where property lookup on objects used as the 'with' statement environment can cause type confusion, potentially leading to arbitrary code execution. This is a memory safety flaw affecting Firefox and Thunderbird clients.

MitigationUpdate affected installations to Firefox 130+, Firefox ESR 128.2+/115.15+, or Thunderbird 128.2+/115.15+ to patch the vulnerability.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
FirefoxWeb browser
Affected:< 130.0
Firefox EsrWeb browser
Affected:< 115.15>= 128.0, < 128.2

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check Firefox version on Windows
    Open Firefox, click Menu (three horizontal lines) > Help > About Firefox. The version number displays next to 'Firefox' at the top of the window.
    Affected if Version shown is below 130.0 (for example 129.x, 128.x, etc.)
  2. Check Firefox version on macOS
    Open Firefox, click Firefox menu > About Firefox. The version number displays in the window that opens.
    Affected if Version shown is below 130.0
  3. Check Firefox ESR version
    Open Firefox ESR, click Help > About Firefox ESR. Note the version number displayed (ESR versions appear as something like 115.x or 128.x).
    Affected if Version is 115.x below 115.15, or 128.x below 128.2 (for example 128.0, 128.1, 115.14)
  4. Check Thunderbird version
    Open Thunderbird, click Help > About Thunderbird. The version number displays in the window that opens.
    Affected if Version is 115.x below 115.15, or 128.x below 128.2

You are affected if you run any Firefox version below 130.0, Firefox ESR below 115.15 or below 128.2, or Thunderbird below 115.15 or below 128.2.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 115.15 / 128.2 / 130.0 or later
Fixed in 115.15128.2130.0
Interim mitigation

Update affected installations to Firefox 130+, Firefox ESR 128.2+/115.15+, or Thunderbird 128.2+/115.15+ to patch the vulnerability.

Recommended fix High confidence

Firefox 130.0, Firefox ESR 128.2, or Firefox ESR 115.15 (depending on which ESR channel is in use)

  1. Check current Firefox version by navigating to about:settings or selecting Help > About Firefox
  2. For Firefox (Standard): Upgrade to version 130.0 or later by selecting Help > Check for Updates and following prompts
  3. For Firefox ESR 128.x: Upgrade to version 128.2 or later by selecting Help > Check for Updates
  4. For Firefox ESR 115.x: Upgrade to version 115.15 or later by selecting Help > Check for Updates
  5. Alternatively, download the appropriate version directly from https://www.mozilla.org/firefox/all/
  6. Restart Firefox after the update completes
  7. Verify the version by navigating to about:settings to confirm the update was successful
Caveat Browser upgrades may cause compatibility issues with older browser extensions or legacy web applications; test in a non-production environment if concerned

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Firefox Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,600
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,560.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2024-8381 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2024-8381 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data