Security readout for executives and security teams
Plain-English summary
COMMAX WebViewer ActiveX Control 2.1.4.5 has a memory corruption flaw that can allow code execution if a user is exposed to malicious content using the control. This matters most where legacy Windows/Internet Explorer-style ActiveX workflows remain in use.
Executive priority
Prioritize review if COMMAX WebViewer is used for building access, camera, or facility monitoring workflows. The risk is high where legacy ActiveX remains enabled, but broad internet-wide exposure is not established by the provided sources.
Technical view
CVE-2021-47719 is a CWE-787 out-of-bounds write/buffer overflow in Commax_WebViewer.ocx. Excessively long string arrays passed through multiple functions can trigger boundary errors and potentially arbitrary code execution. CVSS 4.0 is 8.7, with network attack vector, low complexity, no privileges, and user interaction required.
Likely exposure
Exposure is likely limited to systems with COMMAX WebViewer ActiveX Control version 2.1.4.5 installed and usable by a browser or COM automation context. Modern environments without this legacy ActiveX component are likely unaffected.
Exploitation context
A public Exploit-DB reference exists, and third-party advisories describe exploitability. The provided sources do not show CISA KEV listing or confirmed active exploitation. User interaction is required according to the CVSS vector.
Researcher notes
The CVE record and advisories identify version 2.1.4.5 and describe long string array handling leading to buffer overflow conditions. Evidence for a vendor patch is not present in the supplied bundle. Avoid assuming impact beyond the named ActiveX control.
Mitigation direction
- Identify and remove COMMAX WebViewer ActiveX Control 2.1.4.5 where not required.
- Restrict use of legacy browsers or ActiveX-capable environments.
- Check COMMAX or trusted advisories for vendor update or replacement guidance.
- Limit access to systems that require the control until remediation is confirmed.
Validation and detection
- Inventory endpoints for COMMAX WebViewer ActiveX Control 2.1.4.5.
- Check for Commax_WebViewer.ocx in approved software baselines.
- Confirm whether ActiveX execution is enabled for affected users.
- Review vendor and advisory sources for any newer remediation guidance.
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-787: 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-2021-47719 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
- 8.7 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
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:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N——Primary CVE scoreVulnerability scoring details
Base CVSS 4.0 score
8.7HighVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Source materials
- CVE List V5 sourceCVE List V5
- ExploitDB-50231CVE reference · exploit
- Zero Science Lab Disclosure (ZSL-2021-5663)CVE reference · third-party-advisory
- ReferenceCVE reference · product
- VulnCheck Advisory: CNC_Ctrl DllUnregisterServer f5501 Access ViolationCVE reference · third-party-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.
Out-of-bounds Write
Out-of-bounds Write represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.