CVE-2018-21240
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 · uneditedAn issue was discovered in Foxit Reader and PhantomPDF before 9.2. It allows memory consumption via an ArrayBuffer(0xfffffffe) call.
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 · moderate confidenceA memory consumption vulnerability in Foxit Reader and PhantomPDF versions before 9.2 allows attackers to cause excessive memory allocation via an ArrayBuffer(0xfffffffe) call, which attempts to allocate approximately 4GB of memory, potentially causing application unresponsiveness or crash.
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< 9.2< 9.2CVSS 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
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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 checksWork through these to decide whether this CVE applies to you.
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Verify Foxit product is installedCheck for Foxit Reader or PhantomPDF installation: On Windows, check registry key HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall for Foxit entries, or look for executable at common paths like C:\Program Files\Foxit Software\Foxit Reader\FoxitReader.exeAffected if Neither Foxit Reader nor PhantomPDF is installed on the system
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Identify the specific Foxit productDetermine whether Foxit Reader or PhantomPDF is installed by checking the product name in the registry or the executable file nameAffected if Any Foxit product is present (Reader or PhantomPDF)
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Find installed version numberRight-click the Foxit Reader or PhantomPDF executable, select Properties, and check the Details tab for the Product Version field; alternatively, open the application and go to Help > About to view the versionAffected if Unable to determine version number from the application or file properties
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Compare version against affected rangeCompare your installed version number to the affected range: any version before 9.2 (such as 9.1.x, 9.0.x, or earlier) is vulnerableAffected if Installed version is less than 9.2 (e.g., 9.1.0, 9.0.5, etc.)
You are affected if Foxit Reader or PhantomPDF is installed and the version number is lower than 9.2.
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.
From vendor data9.2
Upgrade Foxit Reader and PhantomPDF to version 9.2 or later to remediate this vulnerability.
- 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-2018-21240 — 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-2018-21240 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
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- 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