Cyber Resilience

CVE-2021-43083

High

Published: 19 December 2021

Published
19 December 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0154 81.7th percentile
Risk Priority 19 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-43083 is a high-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Apache Plc4X. Its CVSS base score is 8.8 (High).

Operationally, ranked in the top 18.3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

Apache PLC4X - PLC4C (Only the C language implementation was effected) was vulnerable to an unsigned integer underflow flaw inside the tcp transport. Users should update to 0.9.1, which addresses this issue. However, in order to exploit this vulnerability, a…

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user would have to actively connect to a mallicious device which could send a response with invalid content. Currently we consider the probability of this being exploited as quite minimal, however this could change in the future, especially with the industrial networks growing more and more together.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

apache
plc4x
≤ 0.9.1

Mitigating Controls

Likely Mitigating Controls AI

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.

addresses: CWE-119

Ongoing control assessments and code testing (static/dynamic analysis, fuzzing) surface memory buffer restriction failures, which are then remediated before release.

addresses: CWE-119

Managed runtimes used by platform-independent applications (e.g., JVM, CLR) enforce memory safety, preventing most buffer overflows that require direct memory manipulation.

addresses: CWE-119

Memory protections (e.g., W^X, ASLR) make exploitation of buffer-boundary violations far harder to turn into code execution.

addresses: CWE-119

Detects exploitation attempts that produce memory corruption, crashes, or anomalous behavior.

References