CVE-2021-41781
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 · uneditedFoxit PDF Reader before 11.1 and PDF Editor before 11.1, and PhantomPDF before 10.1.6, allow attackers to trigger a use-after-free and execute arbitrary code because JavaScript is mishandled.
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 use-after-free vulnerability in Foxit PDF Reader and PDF Editor before version 11.1, and PhantomPDF before version 10.1.6, allows attackers to achieve arbitrary code execution through improper JavaScript handling, potentially via malicious PDF documents.
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>= 11.0, < 11.1>= 11.0, < 11.1< 10.1.6CVSS 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
- Local
- Complexity
- Low
- Privileges
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/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 checksWork through these to decide whether this CVE applies to you.
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Identify Foxit product and versionOpen Foxit PDF Reader, Editor, or PhantomPDF. Go to Help > About Foxit PDF Reader/Editor/PhantomPDF to view the exact version number.Affected if Version is 11.0.x for PDF Reader/Editor, or any version below 10.1.6 for PhantomPDF, or version 11.0.x for PhantomPDF
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Verify JavaScript is enabledIn Foxit application, go to File > Preferences > JavaScript. Confirm if 'Enable JavaScript' option is checked.Affected if JavaScript is enabled in the application settings (this is the attack surface for the vulnerability)
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Check for suspicious PDF handlingReview recent PDF files opened from untrusted sources. In Foxit, go to File > Open to see recent files. No built-in log of executed JavaScript exists.Affected if User has recently opened PDF files from untrusted or unknown sources while JavaScript was enabled
You are affected if your installed Foxit PDF Reader, Editor, or PhantomPDF version falls within 11.0 to <11.1 (for Reader/Editor) or <10.1.6 (for PhantomPDF), AND JavaScript is enabled in the application settings.
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 · scoped10.1.611.1
Upgrade Foxit PDF Reader/Editor to version 11.1 or later, and PhantomPDF to version 10.1.6 or later. Until patched, avoid opening untrusted PDF files.
Foxit PDF Reader 11.1, Foxit PDF Editor 11.1, or PhantomPDF 10.1.6
- 1. Identify the currently installed Foxit product (PDF Reader, PDF Editor, or PhantomPDF) and its version number
- 2. For Foxit PDF Reader or PDF Editor: Navigate to the application's Help menu and select 'Check for Updates' or download version 11.1 or later from the official Foxit website at www.foxit.com
- 3. For PhantomPDF: Download version 10.1.6 or later from the official Foxit website at www.foxit.com
- 4. Run the installer and follow the prompts to upgrade to the fixed version
- 5. After installation, verify the version number matches the fixed release (11.1 or later for Reader/Editor, 10.1.6 or later for PhantomPDF)
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation4.0 h
- Testing2.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-41781 — 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-2021-41781 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