Security readout for executives and security teams
Plain-English summary
A malicious PDF or page could make Foxit PDF Editor misuse memory and run attacker-controlled code as the current user. The known affected product in the bundle is Foxit PDF Editor 11.0.0.49893. Exploitation requires user interaction, so document-heavy teams face the most practical risk.
Executive priority
Treat this as a high-priority workstation remediation item if Foxit PDF Editor is deployed. The business risk is user-driven compromise through documents, not internet-wide unauthenticated exposure. Prioritize teams that routinely receive external PDFs.
Technical view
CVE-2021-34955 is a CWE-416 use-after-free in Foxit PDF Editor’s handling of Stamp Annotation/Annotation objects. The flaw stems from operating on an object without validating that it still exists. Successful exploitation can execute code in the current process context. CVSS is 7.8 high.
Likely exposure
Exposure is most likely on workstations running Foxit PDF Editor 11.0.0.49893, especially users receiving external PDFs or browsing untrusted content. The source bundle does not confirm broader affected versions.
Exploitation context
The bundle does not show CISA KEV listing or other evidence of active exploitation. A remote attacker would still need the target to open a malicious file or visit a malicious page before code execution is possible.
Researcher notes
The record identifies object lifetime validation failure in Annotation object handling and maps to CWE-416. Sources do not provide exploit details, active exploitation evidence, or a specific fixed version in the bundle, so remediation should track Foxit’s bulletin directly.
Mitigation direction
- Inventory endpoints for Foxit PDF Editor, especially version 11.0.0.49893.
- Update Foxit PDF Editor according to Foxit’s security bulletin guidance.
- Limit opening PDFs from untrusted senders until affected systems are remediated.
- Use endpoint controls to reduce impact from user-context code execution.
- Confirm email and web filtering inspect externally supplied PDF content.
Validation and detection
- Check software inventory for Foxit PDF Editor version 11.0.0.49893.
- Confirm installed Foxit builds align with vendor security bulletin guidance.
- Review endpoint detections for suspicious PDF Editor child processes or crashes.
- Validate high-risk users handling external PDFs are remediated first.
- Document residual exposure where affected versions remain installed.
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-2021-34955 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-21-1186CVE 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.