Cyber Resilience

CVE-2021-33719

Critical

Published: 14 September 2021

Published
14 September 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0056 68.6th percentile
Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-33719 is a critical-severity Classic Buffer Overflow (CWE-120) vulnerability in Siemens Siprotec 5 With Cpu Variant Cp050. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 31.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

A vulnerability has been identified in SIPROTEC 5 relays with CPU variants CP050 (All versions < V8.80), SIPROTEC 5 relays with CPU variants CP100 (All versions < V8.80), SIPROTEC 5 relays with CPU variants CP300 (All versions < V8.80). Specially…

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crafted packets sent to port 4443/tcp could cause a Denial-of-Service condition or potential remote code execution.

CWE(s)

Related Threats

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

Affected Assets

siemens
siprotec 5 with cpu variant cp050
≤ 8.80
siemens
siprotec 5 with cpu variant cp100
≤ 8.80
siemens
siprotec 5 with cpu variant cp300
≤ 8.80

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-120

Platform-independent managed code eliminates the need for unchecked native buffer copies that are the root cause of classic buffer overflows.

References