Security readout for executives and security teams
Plain-English summary
CVE-2021-34848 can let an attacker run code through Foxit PDF Reader 11.0.0.49893 if a user opens a malicious PDF or visits a malicious page. The business risk is endpoint compromise through normal document handling, not server-side internet exposure.
Executive priority
Treat as a high-priority workstation remediation item where Foxit Reader is deployed. The issue can enable code execution, but requires user interaction and has no active exploitation evidence in the provided sources.
Technical view
The flaw is in Foxit PDF Reader handling of Annotation objects. The source describes missing validation that an object exists before operations occur, mapped to CWE-416. Successful exploitation can execute code in the current process with high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is likely limited to endpoints running Foxit PDF Reader 11.0.0.49893. Users who handle external PDFs or web content have higher practical exposure because exploitation requires user interaction.
Exploitation context
The bundle does not show CISA KEV listing or cited active exploitation. ZDI identifies the issue as ZDI-CAN-14532/ZDI-21-930. Exploitation requires persuading a user to open a malicious file or visit a malicious page.
Researcher notes
Validation should focus on version exposure and user-driven document attack paths. The provided evidence names the affected build and object-handling flaw, but does not include exploit telemetry, a patch version, or detailed vendor remediation text.
Mitigation direction
- Inventory Foxit PDF Reader installations and identify version 11.0.0.49893.
- Check Foxit security bulletins for the vendor-approved fixed release or mitigation.
- Upgrade affected installations according to Foxit guidance.
- Reduce handling of untrusted PDFs on vulnerable endpoints until remediated.
- Use existing email, web, and endpoint controls to block suspicious PDF delivery.
Validation and detection
- Confirm whether Foxit PDF Reader 11.0.0.49893 exists in asset inventory.
- Compare deployed versions against Foxit's security bulletin guidance.
- Verify upgraded endpoints no longer report the affected version.
- Review endpoint telemetry for suspicious Foxit Reader crashes or document-triggered process activity.
- Confirm high-risk users handling external PDFs are prioritized for remediation.
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-2021-34848 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.foxit.com/support/security-bulletins.htmlCVE reference · x_refsource_MISC
- https://www.zerodayinitiative.com/advisories/ZDI-21-930/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.
Use After Free
Use After Free represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.