Security readout for executives and security teams
Plain-English summary
A malicious PDF or web page could make Foxit Reader run attacker-controlled code after a user opens it. The issue affects Foxit Reader 10.1.1.37576 and requires user interaction, but successful exploitation could compromise the user’s workstation.
Executive priority
Treat this as a high-priority workstation risk where Foxit Reader is deployed. It is not wormable, but a single successful phishing or malicious-document event could allow code execution as the user.
Technical view
CVE-2021-31449 is a CWE-415 use-after-free in Foxit Reader’s handling of U3D objects embedded in PDF files. The flaw involves missing object-existence validation before further free operations, enabling code execution in the current process context.
Likely exposure
Exposure is limited to environments running Foxit Reader 10.1.1.37576, especially users who receive external PDFs or browse web content that can launch PDFs.
Exploitation context
The supplied sources state that exploitation requires a target to visit a malicious page or open a malicious file. CISA KEV is false, and the bundle does not provide evidence of active exploitation.
Researcher notes
The public description identifies U3D PDF object parsing and CWE-415 behavior but does not include detailed patch notes in the bundle. Avoid assuming affected versions beyond Foxit Reader 10.1.1.37576.
Mitigation direction
- Inventory Foxit Reader versions and prioritize 10.1.1.37576.
- Check Foxit security guidance for the fixed version and apply vendor updates.
- Reduce exposure to untrusted PDFs or web-delivered PDFs until patched.
- Use endpoint controls to detect and block suspicious PDF delivery.
Validation and detection
- Confirm whether any endpoints run Foxit Reader 10.1.1.37576.
- Compare installed versions against Foxit’s security bulletin guidance.
- Review endpoint telemetry for suspicious PDF launches or Reader crashes.
- Verify patched systems no longer report the affected version.
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-415: 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-2021-31449 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-21-538/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.
Double Free
Double Free represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.