CVE-2021-25664

Description

A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All versions), Capital Embedded AR Classic R20-11 (All versions < V2303), Nucleus NET (All versions), Nucleus ReadyStart V3 (All versions < V2017.02.4), Nucleus ReadyStart V4 (All versions < V4.1.0), Nucleus Source Code (All versions including affected IPv6 stack). The function that processes the Hop-by-Hop extension header in IPv6 packets and its options lacks any checks against the length field of the header, allowing attackers to put the function into an infinite loop by supplying arbitrary length values.

Category

8.7
CVSS
Severity: High
CVSS 4.0 •
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.52%
Vendor Advisory siemens.com
Affected: Siemens Capital Embedded AR Classic 431-422
Affected: Siemens Capital Embedded AR Classic R20-11
Affected: Siemens Nucleus NET
Affected: Siemens Nucleus ReadyStart V3
Affected: Siemens Nucleus ReadyStart V4
Affected: Siemens Nucleus Source Code
Published at:
Updated at:

References

Link Tags
https://cert-portal.siemens.com/productcert/pdf/ssa-248289.pdf vendor advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-103-05 third party advisory us government resource
https://cert-portal.siemens.com/productcert/html/ssa-248289.html

Frequently Asked Questions

What is the severity of CVE-2021-25664?
CVE-2021-25664 has been scored as a high severity vulnerability.
How to fix CVE-2021-25664?
To fix CVE-2021-25664, 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-2021-25664 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-25664 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-25664?
CVE-2021-25664 affects Siemens Capital Embedded AR Classic 431-422, Siemens Capital Embedded AR Classic R20-11, Siemens Nucleus NET, Siemens Nucleus ReadyStart V3, Siemens Nucleus ReadyStart V4, Siemens Nucleus Source Code.
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