CVE-2021-47894
Published: 23 January 2026
Summary
CVE-2021-47894 is a medium-severity Allocation of Resources Without Limits or Throttling (CWE-770) vulnerability in Switchportmapper (inferred from references). Its CVSS base score is 6.7 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 26.2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 SC-5 (Denial-of-service Protection) and SI-10 (Information Input Validation).
Deeper analysis
CVE-2021-47894 is a denial-of-service vulnerability in Managed Switch Port Mapping Tool version 2.85.2. The flaw arises from inadequate buffer size handling, allowing attackers to crash the application by submitting a 10,000-character oversized buffer into the IP Address or SNMP Community Name fields. It is classified under CWE-770 (Allocation of Resources Without Limits or Throttling) and carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H), indicating high severity primarily due to availability impact.
The vulnerability can be exploited by any unauthenticated remote attacker with network access to the affected application. Exploitation requires low complexity and no user interaction or privileges, enabling the attacker to trigger an application crash through the oversized input, disrupting service availability without affecting confidentiality or integrity.
Advisories and references include the vendor site (switchportmapper.com and its download page), an Exploit-DB proof-of-concept (exploit 49566), and a VulnCheck advisory on the Managed Switch Port Mapping Tool denial-of-service issue. No patches or specific mitigations are mentioned in the available details.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-4300
Vulnerability details
Managed Switch Port Mapping Tool 2.85.2 contains a denial of service vulnerability that allows attackers to crash the application by creating an oversized buffer. Attackers can generate a 10,000-character buffer and paste it into the IP Address and SNMP Community…
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Name fields to trigger the application crash.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Direct application crash via oversized input matches Endpoint DoS via Application or System Exploitation.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly requires validation of inputs in IP Address and SNMP Community Name fields to reject oversized 10,000-character buffers, preventing the application crash.
Implements protections against denial-of-service events like resource exhaustion from oversized input buffers, limiting the impact on application availability.
Mandates timely flaw remediation for vulnerabilities like inadequate buffer size handling, addressing the root cause through patching or updates.