CVE-2021-27393

Description

A vulnerability has been identified in Nucleus NET (All versions), Nucleus ReadyStart V3 (All versions < V2013.08), Nucleus Source Code (Versions including affected DNS modules). The DNS client does not properly randomize UDP port numbers of DNS requests. That could allow an attacker to poison the DNS cache or spoof DNS resolving.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.22%
Vendor Advisory siemens.com
Affected: Siemens Nucleus NET
Affected: Siemens Nucleus ReadyStart V3
Affected: Siemens Nucleus Source Code
Published at:
Updated at:

References

Link Tags
https://cert-portal.siemens.com/productcert/pdf/ssa-201384.pdf vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-27393?
CVE-2021-27393 has been scored as a medium severity vulnerability.
How to fix CVE-2021-27393?
To fix CVE-2021-27393, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-27393 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-27393 is being actively exploited. 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-2021-27393?
CVE-2021-27393 affects Siemens Nucleus NET, Siemens Nucleus ReadyStart V3, Siemens Nucleus Source Code.
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