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).

Published: 2021-08-19 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-36762 is rated Moderate Risk (60.3/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.30%). Core evidence: EPSS rose +1.95% over the last day, indicating growing attacker interest. Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-36762

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.35% 2.30% +1.95%
2 2025-09-28 0.27% 0.35% +0.08%
3 2025-07-16 0.27%

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-36762

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 3.6 [email protected]
7.8 2.0 HIGH
AV:N/AC:L/Au:N/C:C/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
10.0 6.9 [email protected]

Weakness enumeration for CVE-2021-36762

Affected software / configurations for CVE-2021-36762

Vendor Product Version Raw CPE
hcc-embedded nichestack < 4.3 cpe:2.3:a:hcc-embedded:nichestack:*:*:*:*:*:*:*:*

References for CVE-2021-36762

cvelogic Threat Intelligence