CVE-2021-36762
CVE-2021-36762 is a high-severity vulnerability in Hcc-embedded Nichestack with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 7.8
- EPSS exploit prediction: 2% (81st percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Hcc-embedded Nichestack
- Published:
- Last modified:
Description
An issue was discovered in HCC Embedded InterNiche NicheStack through 4.3. The tfshnd():tftpsrv.c TFTP packet processing function doesn't ensure that a filename is adequately '\0' terminated; therefore, a subsequent call to strlen for the filename might read out of bounds of the protocol packet buffer (if no '\0' byte exists within a reasonable range).
Frequently asked questions
- What is CVE-2021-36762?
- An issue was discovered in HCC Embedded InterNiche NicheStack through 4.3. The tfshnd():tftpsrv.c TFTP packet processing function doesn't ensure that a filename is adequately '\0' terminated; therefore, a subsequent call to strlen for the filename might read out of bounds of the protocol packet buffer (if no '\0' byte exists within a reasonable range).
- How severe is CVE-2021-36762?
- CVE-2021-36762 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
- Is CVE-2021-36762 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-36762?
- CVE-2021-36762 affects Hcc-embedded Nichestack. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-36762?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-36762 published?
- CVE-2021-36762 was published on 2021-08-19 and last updated on 2026-06-17.
References
- https://www.forescout.com/blog/new-critical-operational-technology-vulnerabilities-found-on-nichestack/
- https://www.hcc-embedded.com/about/about-interniche
- https://www.kb.cert.org/vuls/id/608209
Affected products (1)
- cpe:2.3:a:hcc-embedded:nichestack:*:*:*:*:*:*:*:*
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