Security readout for executives and security teams
Plain-English summary
A malicious PDF or webpage could cause Foxit PDF Editor to run attacker-controlled code after a user opens it. This is serious for organizations using the listed version because compromise occurs in the user's process context, but the supplied sources do not show active exploitation.
Executive priority
Prioritize remediation where Foxit PDF Editor is used on business endpoints, especially users handling external documents. This is high severity, but urgency should be balanced by the lack of supplied evidence for active exploitation.
Technical view
CVE-2021-34960 is a CWE-416 use-after-free in Foxit PDF Editor's handling of Circle Annotation objects. The flaw comes from operating on an object without validating its existence. ZDI states it can allow code execution in the current process after user interaction.
Likely exposure
Exposure is limited to environments with Foxit PDF Editor 11.0.0.49893 or other versions confirmed by Foxit guidance. The supplied bundle does not establish broader affected versions.
Exploitation context
The attack requires user interaction: opening a malicious file or visiting a malicious page. The CVE is not listed as KEV in the bundle, and no provided source confirms active exploitation.
Researcher notes
Key details are from ZDI and CVE records: UAF, Annotation object handling, current-process code execution, user interaction required, and ZDI-CAN-14362 lineage. Supplied sources do not provide exploit status or a specific fixed version.
Mitigation direction
- Inventory Foxit PDF Editor installations and identify version 11.0.0.49893.
- Check Foxit's security bulletins for fixed versions and vendor instructions.
- Update, remove, or isolate affected installations according to Foxit guidance.
- Reduce exposure to untrusted PDFs and document links until remediation is complete.
Validation and detection
- Confirm whether any endpoint runs Foxit PDF Editor 11.0.0.49893.
- Compare installed Foxit versions with the vendor security bulletin.
- Verify remediation by rechecking application versions after updates.
- Review endpoint telemetry for suspicious Foxit activity tied to untrusted documents.
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-2021-34960 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-21-1191CVE 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.