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Status published
High
CVE-2021-33720
A vulnerability has been identified in SIPROTEC 5 relays with...
Vulnerability Description
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 crafted packets sent to port 4443/tcp could cause a Denial-of-Service condition.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
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Affected Vendor
Siemens
View all reports →Affected Software
SIPROTEC 5 relays with CPU variants CP050, SIPROTEC 5 relays with CPU variants CP100, SIPROTEC 5 relays with CPU variants CP300
Vulnerable Versions:
All versions < V8.80
Timeline
Official Publish:
September 14th, 2021
Last Modified:
August 3rd, 2024
Added to House:
July 21st, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H