How severe is CVE-2023-49621?

CVE-2023-49621 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-49621 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-49621?

CVE-2023-49621 affects Siemens Simatic Cn 4100 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-49621?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2023-49621 have an EU (EUVD) identifier?

Yes. CVE-2023-49621 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-53563.

When was CVE-2023-49621 published?

CVE-2023-49621 was published on 2024-01-09 and last updated on 2026-06-17.

CVE-2023-49621

CVE-2023-49621 is a critical-severity vulnerability in Siemens Simatic Cn 4100 Firmware with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-1392.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2023-53563
Weakness: CWE-1392
Affected product: Siemens Simatic Cn 4100 Firmware
Published: 2024-01-09
Last modified: 2026-06-17

Description

A vulnerability has been identified in SIMATIC CN 4100 (All versions < V2.7). The "intermediate installation" system state of the affected application uses default credential with admin privileges. An attacker could use the credentials to gain complete control of the affected device.

Frequently asked questions

What is CVE-2023-49621?: A vulnerability has been identified in SIMATIC CN 4100 (All versions < V2.7). The "intermediate installation" system state of the affected application uses default credential with admin privileges. An attacker could use the credentials to gain complete control of the affected device.
How severe is CVE-2023-49621?: CVE-2023-49621 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-49621 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-49621?: CVE-2023-49621 affects Siemens Simatic Cn 4100 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-49621?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2023-49621 have an EU (EUVD) identifier?: Yes. CVE-2023-49621 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-53563.
When was CVE-2023-49621 published?: CVE-2023-49621 was published on 2024-01-09 and last updated on 2026-06-17.

References

https://cert-portal.siemens.com/productcert/pdf/ssa-777015.pdf

Affected products (1)

cpe:2.3:o:siemens:simatic_cn_4100_firmware:*:*:*:*:*:*:*:*

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