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Status published
Critical
CVE-2021-34584
CODESYS V2 web server: crafted requests could trigger a buffer over-read (DoS)
Vulnerability Description
Crafted web server requests can be utilised to read partial stack or heap memory or may trigger a denial-of- service condition due to a crash in the CODESYS V2 web server prior to V1.1.9.22.
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
The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:
- This vulnerability was discovered by Tenable Research.
References
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Affected Vendor
CODESYS
View all reports →Affected Software
CODESYS V2
Vulnerable Versions:
all web servers
Timeline
Official Publish:
October 26th, 2021
Last Modified:
September 16th, 2024
Added to House:
July 21st, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H