CVE-2021-25677

Description

A vulnerability has been identified in APOGEE PXC Compact (BACnet) (All versions < V3.5.5), APOGEE PXC Compact (P2 Ethernet) (All versions < V2.8.20), APOGEE PXC Modular (BACnet) (All versions < V3.5.5), APOGEE PXC Modular (P2 Ethernet) (All versions < V2.8.20), Nucleus NET (All versions), Nucleus ReadyStart V3 (All versions < V2017.02.3), Nucleus ReadyStart V3 (All versions < V2017.02.4), Nucleus ReadyStart V4 (All versions < V4.1.0), Nucleus Source Code (Versions including affected DNS modules), SIMOTICS CONNECT 400 (All versions < V0.5.0.0), SIMOTICS CONNECT 400 (All versions >= V0.5.0.0 < V1.0.0.0), TALON TC Compact (BACnet) (All versions < V3.5.5), TALON TC Modular (BACnet) (All versions < V3.5.5). The DNS client does not properly randomize DNS transaction IDs. 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 0.39%
Vendor Advisory siemens.com Vendor Advisory siemens.com
Affected: Siemens APOGEE PXC Compact (BACnet)
Affected: Siemens APOGEE PXC Compact (P2 Ethernet)
Affected: Siemens APOGEE PXC Modular (BACnet)
Affected: Siemens APOGEE PXC Modular (P2 Ethernet)
Affected: Siemens Nucleus NET
Affected: Siemens Nucleus ReadyStart V3
Affected: Siemens Nucleus ReadyStart V3
Affected: Siemens Nucleus ReadyStart V4
Affected: Siemens Nucleus Source Code
Affected: Siemens SIMOTICS CONNECT 400
Affected: Siemens SIMOTICS CONNECT 400
Affected: Siemens TALON TC Compact (BACnet)
Affected: Siemens TALON TC Modular (BACnet)
Published at:
Updated at:

References

Link Tags
https://cert-portal.siemens.com/productcert/pdf/ssa-705111.pdf patch vendor advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-669158.pdf patch vendor advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-180579.pdf

Frequently Asked Questions

What is the severity of CVE-2021-25677?
CVE-2021-25677 has been scored as a medium severity vulnerability.
How to fix CVE-2021-25677?
To fix CVE-2021-25677, 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-2021-25677 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-25677 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-2021-25677?
CVE-2021-25677 affects Siemens APOGEE PXC Compact (BACnet), Siemens APOGEE PXC Compact (P2 Ethernet), Siemens APOGEE PXC Modular (BACnet), Siemens APOGEE PXC Modular (P2 Ethernet), Siemens Nucleus NET, Siemens Nucleus ReadyStart V3, Siemens Nucleus ReadyStart V3, Siemens Nucleus ReadyStart V4, Siemens Nucleus Source Code, Siemens SIMOTICS CONNECT 400, Siemens SIMOTICS CONNECT 400, Siemens TALON TC Compact (BACnet), Siemens TALON TC Modular (BACnet).
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