CVE-2021-34585

Public Exploit
CODESYS V2 web server: crafted requests could trigger a pointer dereference with an invalid address (DoS)

Description

In the CODESYS V2 web server prior to V1.1.9.22 crafted web server requests can trigger a parser error. Since the parser result is not checked under all conditions, a pointer dereference with an invalid address can occur. This leads to a denial of service situation.

Remediation

Solution:

  • CODESYS GmbH has released version V1.1.9.22 of the CODESYS V2 web server to solve the noted vulnerability issues. This version of the CODESYS V2 web server is also part of the CODESYS Development System setup version V2.3.9.68.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.47%
Vendor Advisory codesys.com
Affected: CODESYS CODESYS V2
Published at:
Updated at:

References

Link Tags
https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=16876&token=a3f1d937f95e7034879f4f2ea8e5a99b168256a7&download= vendor advisory
https://www.tenable.com/security/research/tra-2021-47 third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-34585?
CVE-2021-34585 has been scored as a high severity vulnerability.
How to fix CVE-2021-34585?
To fix CVE-2021-34585: CODESYS GmbH has released version V1.1.9.22 of the CODESYS V2 web server to solve the noted vulnerability issues. This version of the CODESYS V2 web server is also part of the CODESYS Development System setup version V2.3.9.68.
Is CVE-2021-34585 being actively exploited in the wild?
It is possible that CVE-2021-34585 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-34585?
CVE-2021-34585 affects CODESYS CODESYS V2.
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