Security readout for executives and security teams
Plain-English summary
This flaw can let an attacker run code through Foxit PDF Reader if a user opens a malicious PDF or visits a malicious page. The provided sources identify Foxit PDF Reader 11.0.1.49938 as affected. No active exploitation evidence is provided.
Executive priority
Treat as a high-priority endpoint remediation item. It is code execution with high confidentiality, integrity, and availability impact, but the provided evidence does not show active exploitation and user interaction is required.
Technical view
CVE-2021-34953 is a CWE-457 uninitialized variable issue in Foxit PDF Reader Annotation object handling. A pointer is accessed without proper initialization, enabling arbitrary code execution in the current process. CVSS 3.0 score is 7.8 with user interaction required.
Likely exposure
Exposure is likely limited to endpoints running Foxit PDF Reader 11.0.1.49938, especially users who receive external PDFs or browse untrusted content.
Exploitation context
Exploitation requires user interaction: opening a malicious file or visiting a malicious page. The provided bundle marks KEV as false and gives no evidence of active exploitation.
Researcher notes
The strongest details come from ZDI and the CVE record. The bundle does not name a fixed version or specific mitigation beyond the vendor security bulletin reference, so remediation should be tied to Foxit guidance.
Mitigation direction
- Inventory Foxit PDF Reader versions across managed endpoints.
- Check Foxit security bulletins for the vendor-approved fixed version or mitigation.
- Update affected Foxit PDF Reader installations through approved software management channels.
- Reduce exposure to unsolicited PDFs until affected systems are updated.
Validation and detection
- Confirm whether Foxit PDF Reader 11.0.1.49938 is installed.
- Review endpoint software inventory for unmanaged Foxit Reader installations.
- Verify updated systems no longer report the affected version.
- Check email and web controls for handling of external PDF attachments.
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-457: 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-2021-34953 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-21-1184CVE 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 of Uninitialized Variable
Use of Uninitialized Variable represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.