Security readout for executives and security teams
Plain-English summary
A malicious PDF or web page could make vulnerable Foxit PhantomPDF installations run attacker-controlled code. The user must open the file or visit the page, so exposure is mainly employee workstations handling untrusted documents.
Executive priority
Treat as high priority for workstation remediation, not a broad server emergency. Risk depends on vulnerable Foxit usage and user exposure to untrusted documents.
Technical view
CVE-2021-31476 is a CWE-843 type confusion flaw in Foxit PhantomPDF 10.1.3.37598 XFA template handling. Insufficient validation of user-supplied data can allow arbitrary code execution in the current process. CVSS v3.0 score is 7.8.
Likely exposure
Organizations are exposed where Foxit PhantomPDF 10.1.3.37598 is installed on user endpoints. Highest concern is users who receive external PDFs, open documents from email, or browse untrusted sites.
Exploitation context
Sources state exploitation requires user interaction: opening a malicious file or visiting a malicious page. The CVE source bundle does not show CISA KEV listing or other evidence of active exploitation.
Researcher notes
This is a client-side RCE class issue tied to XFA template parsing and current-process execution. The provided sources do not name a fixed build, detection indicators, or active exploitation evidence.
Mitigation direction
- Identify endpoints running Foxit PhantomPDF 10.1.3.37598.
- Check Foxit security bulletins for the vendor-designated fixed version.
- Upgrade or remove affected installations according to Foxit guidance.
- Restrict opening untrusted PDFs where remediation is delayed.
- Prioritize endpoints used for external document review.
Validation and detection
- Search software inventory for Foxit PhantomPDF 10.1.3.37598.
- Confirm affected endpoints have been updated or decommissioned.
- Review patch records against Foxit’s security bulletin.
- Check document-handling workflows for external PDF exposure.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-843: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-31476 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.8 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H1.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
7.8HighVector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://www.zerodayinitiative.com/advisories/ZDI-21-614/CVE reference · x_refsource_MISC
- https://www.foxit.com/support/security-bulletins.htmlCVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Access of Resource Using Incompatible Type ('Type Confusion')
Access of Resource Using Incompatible Type ('Type Confusion') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.