FirefoxWeb browser · Mozilla
CVE-2023-4045
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 · uneditedOffscreen Canvas did not properly track cross-origin tainting, which could have been used to access image data from another site in violation of same-origin policy. This vulnerability affects Firefox < 116, Firefox ESR < 102.14, and Firefox ESR < 115.1.
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 confidenceOffscreen Canvas in Firefox did not properly track cross-origin tainting, allowing a malicious page to potentially access image data from another origin in violation of the same-origin policy. This is a client-side browser vulnerability representing a CSP/SOP bypass in the Canvas API.
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
< 116.0>= 102.0, < 102.14>= 115.0, < 115.1
Debian LinuxOperating system
= 11.0= 12.0CVSS 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
- Low
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
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 checksWork through these to decide whether this CVE applies to you.
-
Check installed Firefox versionOpen Firefox and navigate to about:support, or run 'firefox --version' from command lineAffected if Version is < 116.0, OR >= 102.0 and < 102.14, OR >= 115.0 and < 115.1
-
Check Firefox ESR version if applicableOpen Firefox and navigate to about:support, or run 'firefox --version' from command line - ESR versions include 'ESR' in the version stringAffected if Version is ESR and < 102.14 or < 115.1
-
Verify Firefox package version on DebianRun 'dpkg -l | grep firefox' or 'apt list --installed | grep firefox' to list installed Firefox packagesAffected if Package version corresponds to an affected Firefox release per the version ranges
User is affected if Firefox (or Firefox ESR) installed version falls within any of the vulnerable ranges: < 116.0, >= 102.0 to < 102.14, or >= 115.0 to < 115.1
Generated from the published advisory. Verify against your own configuration.
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 · scoped102.14115.1116.0
Upgrade Firefox to version 116 or later, or Firefox ESR to 102.14/115.1 or later to obtain the patched version.
Firefox 116.0+ (regular), Firefox ESR 102.14+, or Firefox ESR 115.1+
- Check current Firefox version by navigating to about:support or using Help > About Firefox
- For Firefox (non-ESR): Upgrade to version 116.0 or later
- For Firefox ESR 102.x: Upgrade to version 102.14 or later
- For Firefox ESR 115.x: Upgrade to version 115.1 or later
- Restart the browser after update to apply changes
- Verify the update was successful by checking the version again
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
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 locallyCheck whether your project pulls in CVE-2023-4045 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2023-4045 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
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.
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.
- 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