CVE-2021-31471
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 · uneditedThis vulnerability allows remote attackers to disclose sensitive information on affected installations of Foxit Reader 10.1.1.37576. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the handling of U3D objects embedded in PDF files. The issue results from the lack of proper validation of user-supplied data, which can result in a read past the end of an allocated object. An attacker can leverage this in conjunction with other vulnerabilities to execute arbitrary code in the context of the current process. Was ZDI-CAN-12955.
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 confidenceThis is an out-of-bounds read vulnerability in Foxit Reader's handling of U3D (3D) objects embedded in PDF files. The lack of proper validation of user-supplied data during PDF parsing allows reading past the end of an allocated object, resulting in sensitive information disclosure. While exploitable only with user interaction (opening a malicious PDF), this vulnerability can be chained with other flaws to achieve arbitrary code execution in the context of the current process.
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<= 9.7.4.29600>= 10.0, <= 10.0.1.37598CVSS 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
- None
- Availability
- None
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/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 if Foxit Reader is installedLook for Foxit Reader installation directory (typically C:\Program Files\Foxit Software\Foxit Reader or C:\Program Files (x86)\Foxit Software\Foxit Reader) or check Windows Registry under HKEY_LOCAL_MACHINE\SOFTWARE\FoxitSoftware or HKEY_CURRENT_USER\SOFTWARE\FoxitSoftwareAffected if Foxit Reader is found on the system
-
Locate the Foxit Reader executable and determine its versionNavigate to the Foxit Reader installation folder, right-click on FoxitReader.exe, select Properties, and view the Details tab for the File VersionAffected if Cannot locate FoxitReader.exe or version information is unavailable
-
Compare installed version against affected rangesExtract the full version number (e.g., 9.7.4.29600 or 10.0.1.37598) from the file properties and compare against: version <= 9.7.4.29600 OR (version >= 10.0 AND version <= 10.0.1.37598)Affected if Installed version falls within the affected ranges (9.7.4.29600 and below, or between 10.0.0.00000 and 10.0.1.37598 inclusive)
-
Identify if U3D/3D object parsing is in useThis vulnerability affects the built-in U3D (3D) parser which is enabled by default in Foxit Reader. No additional configuration check needed - the vulnerability triggers when opening any PDF containing U3D objectsAffected if User opens PDF files with embedded U3D/3D content using an affected Foxit Reader version
User is affected if Foxit Reader is installed with a version number matching <= 9.7.4.29600 or between 10.0.0.00000 and 10.0.1.37598, and the application is used to open PDF files (particularly those containing 3D/U3D objects).
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 dataUsers should avoid opening PDF files from untrusted sources and ensure Foxit Reader is updated to the latest patched version once available from the vendor.
- Consultation3.0 h
- Implementation2.0 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 $2,304.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-31471 — 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-2021-31471 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