CVE-2021-34583
CVSS v3
7.5
HIGH
EPSS Score
8.4 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
Crafted web server requests may cause a heap-based buffer overflow and could therefore trigger a denial-of- service condition due to a crash in the CODESYS V2 web server prior to V1.1.9.22.
Technical details
- Published
- 2021-10-26
Frequently asked questions
What is CVE-2021-34583?
Crafted web server requests may cause a heap-based buffer overflow and could therefore trigger a denial-of- service condition due to a crash in the CODESYS V2 web server prior to V1.1.9.22.
Is CVE-2021-34583 actively exploited?
Active exploitation of CVE-2021-34583 has not been confirmed. Its EPSS score was 8.4% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-34583?
CVE-2021-34583 has a CVSS v3 base score of 7.5 (HIGH severity).
Is CVE-2021-34583 affecting your environment?
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