Security readout for executives and security teams
Plain-English summary
CVE-2021-31447 affects Foxit Reader 10.1.1.37576. A crafted PDF or malicious page can cause the reader to read memory outside an expected object, potentially exposing sensitive information. The source says it could support code execution when chained with other vulnerabilities, but this CVE alone is rated low severity.
Executive priority
Treat this as a targeted legacy endpoint hygiene issue, not an emergency. Patch or retire affected Foxit Reader installations during the next security maintenance cycle, with faster action for teams receiving external PDFs.
Technical view
The flaw is a CWE-125 out-of-bounds read in Foxit Reader U3D object handling inside PDF files. Exploitation requires user interaction and can disclose limited process memory. The CVSS 3.0 score is 3.3, with local attack vector and low confidentiality impact.
Likely exposure
Exposure is likely limited to endpoints running Foxit Reader 10.1.1.37576, especially users who open untrusted PDFs or view PDFs from web content. The bundle does not identify server-side exposure or additional affected versions.
Exploitation context
The provided sources require the victim to open a malicious file or visit a malicious page. CISA KEV status is false, and the bundle provides no evidence of active exploitation in the wild.
Researcher notes
ZDI tracks this as ZDI-21-536 and ZDI-CAN-13269. The key technical issue is malformed U3D object parsing leading to an out-of-bounds read. The bundle does not name a fixed version, exploit sample, or standalone code execution path.
Mitigation direction
- Inventory Foxit Reader versions and identify any 10.1.1.37576 installations.
- Check Foxit security bulletins for the vendor-supported update or guidance.
- Prioritize updating users who handle external PDFs or web-delivered documents.
- Restrict opening untrusted PDFs where update timing is delayed.
- Keep endpoint detection and document-handling controls current.
Validation and detection
- Confirm whether Foxit Reader 10.1.1.37576 is installed on managed endpoints.
- Review software inventory for unmanaged or legacy Foxit Reader deployments.
- Verify update status against Foxit’s published security bulletin.
- Confirm high-risk user groups are not relying on the affected version.
- Check whether PDF handling defaults expose users to untrusted files.
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-2021-31447 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
- Low
- CVSS
- 3.3 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
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:L/I:N/A:N1.81.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
3.3LowVector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
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-21-536/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.