5.3
MEDIUM
CVE-2021-27393
Nucleus NET/Tiba DNS Port Randomization Vulnerability
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.

INFO

Published Date :

April 22, 2021, 9:15 p.m.

Last Modified :

Nov. 21, 2024, 5:57 a.m.

Remotely Exploitable :

Yes !

Impact Score :

1.4

Exploitability Score :

3.9
Affected Products

The following products are affected by CVE-2021-27393 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Siemens nucleus_net
2 Siemens nucleus_readystart_v3
3 Siemens nucleus_source_code
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-27393.

URL Resource
https://cert-portal.siemens.com/productcert/pdf/ssa-201384.pdf Vendor Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-201384.pdf Vendor Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-27393 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-27393 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://cert-portal.siemens.com/productcert/pdf/ssa-201384.pdf
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Modified Analysis by [email protected]

    Apr. 22, 2022

    Action Type Old Value New Value
    Changed CPE Configuration OR *cpe:2.3:a:siemens:capital_vstar:-:*:*:*:*:*:*:* *cpe:2.3:a:siemens:nucleus_net:*:*:*:*:*:*:*:* *cpe:2.3:a:siemens:nucleus_readystart:*:*:*:*:*:*:*:* versions up to (excluding) 2013.08 *cpe:2.3:a:siemens:nucleus_source_code:-:*:*:*:*:*:*:* *cpe:2.3:o:siemens:nucleus_rtos:-:*:*:*:*:*:*:* OR *cpe:2.3:a:siemens:nucleus_net:*:*:*:*:*:*:*:* *cpe:2.3:a:siemens:nucleus_readystart_v3:*:*:*:*:*:*:*:* versions up to (excluding) 2013.08 *cpe:2.3:a:siemens:nucleus_source_code:-:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Jan. 11, 2022

    Action Type Old Value New Value
    Changed Description A vulnerability has been identified in Capital VSTAR (Versions including affected DNS modules), 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. 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.
  • CVE Modified by [email protected]

    Nov. 17, 2021

    Action Type Old Value New Value
    Changed Description A vulnerability has been identified in Nucleus NET (All versions), Nucleus RTOS (versions including affected DNS modules), Nucleus ReadyStart (All versions < V2013.08), Nucleus Source Code (versions including affected DNS modules), VSTAR (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. A vulnerability has been identified in Capital VSTAR (Versions including affected DNS modules), 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.
  • Modified Analysis by [email protected]

    Nov. 11, 2021

    Action Type Old Value New Value
    Changed CPE Configuration OR *cpe:2.3:a:siemens:nucleus_net:*:*:*:*:*:*:*:* *cpe:2.3:a:siemens:nucleus_readystart:*:*:*:*:*:*:*:* versions up to (excluding) 2013.08 *cpe:2.3:a:siemens:nucleus_source_code:-:*:*:*:*:*:*:* *cpe:2.3:a:siemens:vstar:-:*:*:*:*:*:*:* *cpe:2.3:o:siemens:nucleus_rtos:-:*:*:*:*:*:*:* OR *cpe:2.3:a:siemens:capital_vstar:-:*:*:*:*:*:*:* *cpe:2.3:a:siemens:nucleus_net:*:*:*:*:*:*:*:* *cpe:2.3:a:siemens:nucleus_readystart:*:*:*:*:*:*:*:* versions up to (excluding) 2013.08 *cpe:2.3:a:siemens:nucleus_source_code:-:*:*:*:*:*:*:* *cpe:2.3:o:siemens:nucleus_rtos:-:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Nov. 10, 2021

    Action Type Old Value New Value
    Changed Description A vulnerability has been identified in Capital VSTAR (Versions including affected DNS modules), 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. A vulnerability has been identified in Nucleus NET (All versions), Nucleus RTOS (versions including affected DNS modules), Nucleus ReadyStart (All versions < V2013.08), Nucleus Source Code (versions including affected DNS modules), VSTAR (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.
  • CVE Modified by [email protected]

    Nov. 09, 2021

    Action Type Old Value New Value
    Changed Description A vulnerability has been identified in Nucleus NET (All versions), Nucleus RTOS (versions including affected DNS modules), Nucleus ReadyStart (All versions < V2013.08), Nucleus Source Code (versions including affected DNS modules), VSTAR (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. A vulnerability has been identified in Capital VSTAR (Versions including affected DNS modules), 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.
  • Initial Analysis by [email protected]

    Apr. 30, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:N/I:P/A:N)
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
    Changed Reference Type https://cert-portal.siemens.com/productcert/pdf/ssa-201384.pdf No Types Assigned https://cert-portal.siemens.com/productcert/pdf/ssa-201384.pdf Vendor Advisory
    Added CWE NIST CWE-330
    Added CPE Configuration OR *cpe:2.3:a:siemens:nucleus_net:*:*:*:*:*:*:*:* *cpe:2.3:a:siemens:nucleus_readystart:*:*:*:*:*:*:*:* versions up to (excluding) 2013.08 *cpe:2.3:a:siemens:nucleus_source_code:-:*:*:*:*:*:*:* *cpe:2.3:a:siemens:vstar:-:*:*:*:*:*:*:* *cpe:2.3:o:siemens:nucleus_rtos:-:*:*:*:*:*:*:*
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-27393 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-27393 weaknesses.

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.08 }} 0.01%

score

0.34844

percentile

CVSS31 - Vulnerability Scoring System
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