CVE-2021-47895
Published: 23 January 2026
Summary
CVE-2021-47895 is a high-severity Allocation of Resources Without Limits or Throttling (CWE-770) vulnerability in Nsasoft Nsauditor. Its CVSS base score is 7.5 (High).
Operationally, ranked at the 16.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
Threat & Defense Details
Likely Mitigating ControlsAI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
This control implements explicit throttling on session allocation, addressing the weakness of allocating resources without limits.
Plan testing exercises resource allocation limits and throttling during simulated failures, directly addressing weaknesses that allow unbounded resource use.
Contingency plan updates ensure recovery strategies address unbounded resource allocation, making it harder for attackers to exploit lack of throttling to cause prolonged outages.
Provides continuity when unbounded resource allocation at the primary site leads to exhaustion and downtime.
Alternate services allow operations to continue when primary allocation of resources lacks limits or throttling.
Explicit planning of security-related actions requires defining limits, windows, and resource allocations, making allocation without throttling far less likely.
Measures of performance include tracking allocation behavior and throttling effectiveness, reducing the window for resource exhaustion attacks.
Imposes an inactivity-based limit on network resource allocation, throttling the number of concurrently held connections.
NVD Description
Nsauditor 3.2.2.0 contains a denial of service vulnerability that allows attackers to crash the application by overwriting the Event Description field with a large buffer. Attackers can generate a 10,000-character 'U' buffer and paste it into the Event Description field…
more
to trigger an application crash.
Deeper analysisAI
CVE-2021-47895 is a denial-of-service vulnerability in Nsauditor version 3.2.2.0, a network security auditing tool. The flaw allows attackers to crash the application by overwriting the Event Description field with a large buffer, such as a 10,000-character string of 'U' characters pasted into the field. This triggers an unhandled buffer overflow, leading to application termination, and is classified under CWE-770 (Allocation of Resources Without Limits or Throttling).
The vulnerability has 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 it is exploitable over the network with low complexity, requiring no privileges or user interaction, and results in high availability impact with no confidentiality or integrity effects. Any remote attacker can achieve this by sending the oversized input to a targeted Nsauditor instance, causing a crash and denying service to legitimate users.
Advisories from VulnCheck and a proof-of-concept exploit on Exploit-DB (ID 49568) document the issue, with the vendor site at nsauditor.com providing product details but no specific patch information in the available references. Security practitioners should upgrade to newer versions if available or discontinue use of the affected release.
A public PoC exploit confirms practical exploitability, though no evidence of widespread real-world attacks is noted in the provided data.
Details
- CWE(s)