dbcve.org
FirefoxWeb browser · Mozilla

CVE-2023-5168

CRITICAL · 9.8 CVSS v3.1 Published 2023-09-27
Fix available
A fix is available. Upgrade to 115.3 / 118 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 compromised content process could have provided malicious data to `FilterNodeD2D1` resulting in an out-of-bounds write, leading to a potentially exploitable crash in a privileged process. *This bug only affects Firefox on Windows. Other operating systems are unaffected.* This vulnerability affects Firefox < 118, Firefox ESR < 115.3, and Thunderbird < 115.3.

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

This is a memory corruption vulnerability in Firefox's Direct2D graphics rendering component (FilterNodeD2D1) on Windows. A compromised content process can send malicious data through IPC that triggers an out-of-bounds write in a privileged process, potentially leading to arbitrary code execution.

MitigationUpgrade to Firefox 118+, Firefox ESR 115.3+, or Thunderbird 115.3+ to remediate. This is a Windows-only issue affecting the graphics rendering pipeline.

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:< 118
Firefox EsrWeb browser
Affected:< 115.3
ThunderbirdApplication
Affected:< 115.3

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. Confirm Windows operating system
    Run 'systeminfo' or check System Properties. This vulnerability exists only on Windows due to its reliance on the Direct2D graphics API.
    Affected if The environment is Windows and has Firefox or Thunderbird installed
  2. Identify installed Mozilla product
    Check for Firefox or Thunderbird in Program Files or Program Files (x86). In PowerShell, query registry: Get-ItemProperty HKLM:\SOFTWARE\Mozilla\Mozilla Firefox or HKLM:\SOFTWARE\Mozilla\Thunderbird
    Affected if Firefox or Thunderbird is present on the Windows system
  3. Determine product version
    Open the application, go to Help > About, or run 'firefox --version' or 'thunderbird --version' from command line
    Affected if A version is returned that can be compared against affected ranges
  4. Compare against affected versions
    For Firefox: verify version is less than 118. For Firefox ESR: verify version is less than 115.3. For Thunderbird: verify version is less than 115.3
    Affected if Installed version is Firefox < 118, Firefox ESR < 115.3, or Thunderbird < 115.3 on Windows

A Windows user is affected if they are running any version of Firefox below 118, Firefox ESR below 115.3, or Thunderbird below 115.3.

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 115.3 / 118 or later
Fixed in 115.3118
Interim mitigation

Upgrade to Firefox 118+, Firefox ESR 115.3+, or Thunderbird 115.3+ to remediate. This is a Windows-only issue affecting the graphics rendering pipeline.

Recommended fix High confidence

Firefox 118, Firefox ESR 115.3, or Thunderbird 115.3 (or later)

  1. Identify which Mozilla product needs updating (Firefox, Firefox ESR, or Thunderbird)
  2. Open the application and navigate to Menu > Help > About to check current version
  3. If version is below 118 (Firefox) or below 115.3 (Firefox ESR/Thunderbird), the update check should automatically download the fixed version
  4. Alternatively, manually download the fixed version from the official Mozilla website: https://www.mozilla.org/
  5. After downloading, close all browser/windows and run the installer
  6. Restart the application and verify the version has been updated to 118+ (Firefox) or 115.3+ (Firefox ESR/Thunderbird)
  7. Note: This vulnerability only affects Windows; macOS and Linux users are not impacted
Caveat Mozilla minor version updates typically do not introduce breaking changes; however, some legacy extensions or add-ons may need updating

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

Fix this in Firefox Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,040
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,664.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2023-5168 — 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-2023-5168 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