Security readout for executives and security teams
Plain-English summary
A malicious PDF or web page could make vulnerable Foxit PDF Reader run code as the signed-in user. The user must open the file or visit the page, but successful exploitation could compromise confidentiality, integrity, and availability on that workstation.
Executive priority
Treat as a high-priority endpoint remediation item, not an internet-facing emergency. The business risk is user-driven compromise through malicious documents, so focus on exposed workstations and vendor-confirmed updates.
Technical view
CVE-2021-34974 is a CWE-416 use-after-free in Foxit PDF Reader annotation object handling. The flaw is tied to missing validation that an object exists before operations are performed. ZDI identifies affected Foxit PDF Reader 11.0.1.49938 and arbitrary code execution in the current process.
Likely exposure
Exposure is most likely on endpoints running Foxit PDF Reader 11.0.1.49938, especially where users receive PDFs from email, web downloads, portals, or external partners. The provided sources do not establish server-side exposure or broader Foxit product impact.
Exploitation context
User interaction is required: the target must open a malicious file or visit a malicious page. The bundle does not cite CISA KEV listing or any active exploitation evidence, so active exploitation should not be assumed from these sources.
Researcher notes
The evidence supports a use-after-free in Annotation object handling, ZDI-CAN-15167, with CVSS 3.0 score 7.8. Fixed-version details are not present in the provided bundle, so remediation should be tied to Foxit’s bulletin rather than inferred.
Mitigation direction
- Inventory Foxit PDF Reader installations and flag version 11.0.1.49938.
- Check Foxit security bulletins for the vendor-designated fixed release and update path.
- Prioritize updating exposed user workstations that handle external PDFs.
- Limit opening untrusted PDFs until vendor guidance is applied.
- Use endpoint controls to monitor suspicious Reader child processes.
Validation and detection
- Confirm installed Foxit PDF Reader versions across managed endpoints.
- Verify whether any endpoint reports version 11.0.1.49938.
- Review Foxit security bulletin details before closing remediation tickets.
- Check whether users commonly open external PDFs in Foxit Reader.
- Document that no cited source confirms active exploitation.
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-2021-34974 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-21-1205CVE 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.