CVE-2021-34586
In the CODESYS V2 web server prior to V1.1.9.22 crafted web server requests may cause a Null pointer dereference in the CODESYS web server and may result in a denial-of-service condition.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 13.7%, higher than 97% of all known CVEs. Patch or mitigate before the next change window.
Description
In the CODESYS V2 web server prior to V1.1.9.22 crafted web server requests may cause a Null pointer dereference in the CODESYS web server and may result in a denial-of-service condition.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 13.74% probability · 97th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-476
- Affected
- wago/750-823 firmware · wago/750-829 firmware · wago/750-831 firmware · wago/750-832 firmware · wago/750-852 firmware · wago/750-862 firmware · wago/750-880 firmware · wago/750-881 firmware · wago/750-882 firmware · wago/750-885 firmware · wago/750-889 firmware · wago/750-890 firmware · wago/750-891 firmware · wago/750-893 firmware · wago/750-8202 firmware · wago/750-8203 firmware · wago/750-8204 firmware · wago/750-8206 firmware · wago/750-8207 firmware · wago/750-8208 firmware · +8 more
- Source
- info@cert.vde.com
EPSS moved from 14.1% on 23 September 2026 to 13.7% on 3 November 2026. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”.
References
- https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=16876&token=a3f1d937f95e7034879f4f2ea8e5a99b168256a7&download=Vendor Advisory
- https://www.tenable.com/security/research/tra-2021-47Exploit, Third Party Advisory
- https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=16876&token=a3f1d937f95e7034879f4f2ea8e5a99b168256a7&download=Vendor Advisory
- https://www.tenable.com/security/research/tra-2021-47Exploit, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.