Security readout for executives and security teams
Plain-English summary
This CVE affects HCC Embedded InterNiche NicheStack through 4.3. A malformed TFTP packet can make the server read beyond the packet buffer while checking a filename. Business urgency depends on whether products in your environment embed NicheStack and expose TFTP.
Executive priority
Treat this as an asset-discovery and vendor-coordination priority, not a confirmed emergency from the supplied evidence. Escalate if NicheStack-based devices expose TFTP on production or OT networks.
Technical view
In tfshnd() within tftpsrv.c, TFTP filename handling does not ensure adequate null termination before strlen() is called. If the packet lacks a null byte within the expected range, strlen() may read out of bounds from the protocol packet buffer. The cited record does not specify CVSS, CWE, or final impact.
Likely exposure
Likely exposure is embedded, industrial, or operational technology products that include InterNiche NicheStack through 4.3 and have TFTP reachable. The source bundle does not enumerate OEM products, CPEs, or vulnerable device models.
Exploitation context
The bundle does not provide evidence of active exploitation, and KEV is false. The issue is remotely reachable only where the affected TFTP service is accessible, but exploitability and impact are not fully characterized in the provided sources.
Researcher notes
Evidence is limited to the CVE description and referenced advisories. No CVSS, CWE, CPEs, affected OEM list, exploit status, or patch details are included in the bundle. Avoid assuming impact beyond the documented out-of-bounds read.
Mitigation direction
- Identify products that embed InterNiche NicheStack through 4.3.
- Check HCC Embedded, CERT/CC, and OEM advisories for fixes or mitigations.
- Restrict or disable TFTP where it is not operationally required.
- Block untrusted network access to exposed TFTP services.
- Prioritize compensating controls for OT and unmanaged embedded assets.
Validation and detection
- Inventory embedded and OT devices for NicheStack or InterNiche components.
- Confirm whether TFTP is enabled and network-reachable.
- Review vendor firmware advisories against affected NicheStack versions.
- Check boundary controls for UDP TFTP exposure.
- Document products where component evidence is unavailable.
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-2021-36762 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://www.hcc-embedded.com/about/about-internicheCVE reference · x_refsource_MISC
- https://www.forescout.com/blog/new-critical-operational-technology-vulnerabilities-found-on-nichestack/CVE reference · x_refsource_MISC
- VU#608209CVE reference · third-party-advisory, x_refsource_CERT-VN
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.