Security readout for executives and security teams
Plain-English summary
This issue can crash Zoom's On-Premise Meeting Connector Controller when it receives certain network packets. For businesses using this on-prem Zoom component, the main risk is meeting service disruption, not confirmed data compromise.
Executive priority
Treat as a service availability issue for organizations dependent on Zoom on-prem meeting infrastructure. Prioritize upgrade and exposure review if the component is internet-facing, broadly reachable, or supports critical communications.
Technical view
The Zone Controller service fails to verify the cnt field in incoming network packets. In versions before 4.6.358.20210205, this can cause resource exhaustion and a system crash. No CVSS, CWE, or detailed prerequisites are provided in the source bundle.
Likely exposure
Exposure is limited to organizations running Zoom On-Premise Meeting Connector Controller before 4.6.358.20210205. Risk depends on whether the Zone Controller service can receive untrusted or poorly controlled network traffic; the sources do not define required network reachability.
Exploitation context
The source bundle does not show CISA KEV listing, active exploitation, exploit availability, or weaponized public details. The documented impact is denial of service through resource exhaustion and crash, not privilege escalation or code execution.
Researcher notes
Evidence is sparse: the bundle provides affected version information and root cause, but no CVSS vector, CWE, packet format detail, authentication requirement, or exploit status. Avoid assuming broader Zoom product exposure beyond the named on-prem controller.
Mitigation direction
- Upgrade affected controllers to version 4.6.358.20210205 or later.
- Check Zoom's security bulletin for any newer vendor guidance.
- Restrict network access to the Zone Controller service where operationally possible.
- Monitor controller stability and unexpected restarts until remediation is complete.
Validation and detection
- Inventory deployed Zoom On-Premise Meeting Connector Controller versions.
- Confirm no controller remains below version 4.6.358.20210205.
- Review logs or monitoring for unexplained controller crashes.
- Verify network paths to the Zone Controller service are limited to expected sources.
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.
CVE-2021-34415 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
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
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 and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://explore.zoom.us/en/trust/security/security-bulletin/CVE reference · x_refsource_CONFIRM
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.