Security readout for executives and security teams
Plain-English summary
CVE-2021-34964 is a remote code execution flaw in Foxit PDF Editor. An attacker would need a user to open a malicious file or visit a malicious page. Successful exploitation could run code with the user’s privileges, creating confidentiality, integrity, and availability risk on affected workstations.
Executive priority
Treat this as a high-priority workstation remediation item where Foxit PDF Editor is deployed. The business risk depends on endpoint prevalence and exposure to external PDFs, not network reachability alone.
Technical view
The flaw is a CWE-416 use-after-free in Foxit PDF Editor’s handling of Polygon Annotation objects. Sources identify affected version 11.0.0.49893. The issue stems from failing to validate that an object still exists before operating on it, enabling code execution in the current process context.
Likely exposure
Exposure is most likely on endpoints running Foxit PDF Editor 11.0.0.49893, especially where users open external PDFs or browser-delivered documents.
Exploitation context
The provided sources do not show CISA KEV listing or active exploitation. Exploitation requires user interaction: opening a malicious file or visiting a malicious page. No exploit procedure is provided or needed for risk evaluation.
Researcher notes
Evidence is clear on vulnerability class, affected product/version, user interaction, and impact. The provided bundle does not include a named fixed version, patch date, or active exploitation evidence, so remediation should be tied to Foxit’s advisory.
Mitigation direction
- Inventory Foxit PDF Editor installations and identify version 11.0.0.49893.
- Check Foxit security bulletins for the vendor’s fixed version or mitigation guidance.
- Update affected installations according to Foxit’s published guidance.
- Limit handling of untrusted PDFs until affected endpoints are remediated.
- Prioritize controls around email and web-delivered PDF attachments.
Validation and detection
- Confirm installed Foxit PDF Editor versions across managed endpoints.
- Compare findings against the affected version listed in CVE and ZDI records.
- Review Foxit’s security bulletin page for the applicable remediation entry.
- Verify security tooling alerts on suspicious PDF Editor child processes or crashes.
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-416: 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-2021-34964 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
- ZDI-21-1195CVE reference · x_research-advisory
- vendor-provided URLCVE reference · vendor-advisory
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.
Use After Free
Use After Free represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.