Security readout for executives and security teams
Plain-English summary
CVE-2021-31468 is a high-severity Foxit Reader flaw that can let an attacker run code when a user opens a malicious PDF or visits a malicious page. It affects Foxit Reader 10.1.3.37598 and requires user interaction.
Executive priority
Treat this as a patch-management priority for endpoints using Foxit Reader, especially user workstations handling external documents. It is not marked as actively exploited in the provided evidence.
Technical view
The flaw is in handling U3D files embedded in PDF documents. Improper validation of user-supplied data can cause a read past the end of an allocated data structure, mapped to CWE-125. ZDI says this can lead to code execution in the current process.
Likely exposure
Exposure is limited to environments running Foxit Reader 10.1.3.37598. Risk is higher where users receive external PDFs, browse untrusted sites, or use Foxit Reader as the default PDF handler.
Exploitation context
The sources describe remote attacker delivery through a malicious page or file, but user interaction is required. The bundle does not indicate CISA KEV listing or active exploitation evidence.
Researcher notes
Do not assume broader Foxit product impact from the provided sources. Validation should focus on the named Reader version and U3D-in-PDF attack surface. The available evidence does not name exploit campaigns.
Mitigation direction
- Inventory endpoints for Foxit Reader 10.1.3.37598.
- Review Foxit’s security bulletin for vendor guidance and fixed versions.
- Prioritize updates or removal where the affected version is present.
- Reduce handling of untrusted PDFs until remediation is complete.
- Use endpoint controls to limit risky document execution paths.
Validation and detection
- Confirm whether Foxit Reader 10.1.3.37598 exists on managed endpoints.
- Verify remediated systems no longer report the affected version.
- Check whether Foxit Reader is the default PDF handler for external files.
- Review email and web controls for suspicious PDF delivery attempts.
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-125: 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-2021-31468 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.foxitsoftware.com/support/security-bulletins.phpCVE reference · x_refsource_MISC
- https://www.zerodayinitiative.com/advisories/ZDI-21-557/CVE 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.
Out-of-bounds Read
Out-of-bounds Read represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.