How severe is CVE-2020-25241?

CVE-2020-25241 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-25241 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-25241?

CVE-2020-25241 primarily affects Siemens Simatic Mv440 Sr Firmware. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-25241?

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

When was CVE-2020-25241 published?

CVE-2020-25241 was published on 2021-03-15 and last updated on 2026-06-17.

CVE-2020-25241

CVE-2020-25241 is a high-severity vulnerability in Siemens Simatic Mv440 Sr Firmware with a CVSS 3.x base score of 7.5. 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-129.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-129
Affected product: Siemens Simatic Mv440 Sr Firmware
Published: 2021-03-15
Last modified: 2026-06-17

Description

A vulnerability has been identified in SIMATIC MV400 family (All Versions < V7.0.6). The underlying TCP stack of the affected products does not correctly validate the sequence number for incoming TCP RST packages. An attacker could exploit this to terminate arbitrary TCP sessions.

Frequently asked questions

What is CVE-2020-25241?: A vulnerability has been identified in SIMATIC MV400 family (All Versions < V7.0.6). The underlying TCP stack of the affected products does not correctly validate the sequence number for incoming TCP RST packages. An attacker could exploit this to terminate arbitrary TCP sessions.
How severe is CVE-2020-25241?: CVE-2020-25241 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-25241 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-25241?: CVE-2020-25241 primarily affects Siemens Simatic Mv440 Sr Firmware. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-25241?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-25241 published?: CVE-2020-25241 was published on 2021-03-15 and last updated on 2026-06-17.

References

https://cert-portal.siemens.com/productcert/pdf/ssa-599268.pdf

Affected products (7)

cpe:2.3:o:siemens:simatic_mv440_sr_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_mv440_hr_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_mv440_ur_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_mv420_sr-b_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_mv420_sr-p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_mv420_sr-b_body_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_mv420_sr-p_body_firmware:*:*:*:*:*:*:*:*

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