How severe is CVE-2021-44695?

CVE-2021-44695 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-44695 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-44695?

CVE-2021-44695 primarily affects Siemens Simatic S7-plcsim Advanced Firmware. In total, 96 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-44695?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-44695 published?

CVE-2021-44695 was published on 2022-12-13 and last updated on 2026-06-17.

CVE-2021-44695

CVE-2021-44695 is a medium-severity vulnerability in Siemens Simatic S7-plcsim Advanced Firmware with a CVSS 3.x base score of 4.9. 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-1286.

Key facts

Severity: Medium (CVSS 3.x base score 4.9)
EPSS exploit prediction: 1% (49th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1286
Affected product: Siemens Simatic S7-plcsim Advanced Firmware
Published: 2022-12-13
Last modified: 2026-06-17

Description

Affected devices don't process correctly certain special crafted packets sent to port 102/tcp, which could allow an attacker to cause a denial of service in the device.

Frequently asked questions

What is CVE-2021-44695?: Affected devices don't process correctly certain special crafted packets sent to port 102/tcp, which could allow an attacker to cause a denial of service in the device.
How severe is CVE-2021-44695?: CVE-2021-44695 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-44695 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-44695?: CVE-2021-44695 primarily affects Siemens Simatic S7-plcsim Advanced Firmware. In total, 96 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-44695?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-44695 published?: CVE-2021-44695 was published on 2022-12-13 and last updated on 2026-06-17.

References

https://cert-portal.siemens.com/productcert/pdf/ssa-382653.pdf

Affected products (96)

cpe:2.3:o:siemens:simatic_s7-plcsim_advanced_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_1211c_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_1212c_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_1212fc_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_1214_fc_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_1214c_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_1214fc_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_1215_fc_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_1215c_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_1215fc_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_1217c_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_12_1211c_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_12_1212c_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_12_1212fc_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_12_1214c_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_12_1214fc_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_12_1215c_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_12_1215fc_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1200_cpu_12_1217c_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:siplus_s7-1200_cp_1243-1_rail_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:siplus_s7-1200_cp_1243-1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1507s_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1507s_f_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1508s_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1508s_f_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1510sp_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1510sp-1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1511-1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1511-1_pn_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1511c_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1511c-1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1511f-1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1511f-1_pn_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1511t-1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1511tf-1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1512c_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1512c-1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1512sp-1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1512spf-1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1513-1_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Siemens Simatic S7-plcsim Advanced Firmware

CVE-2022-38465 — Critical (CVSS 9.3): A vulnerability has been identified in SIMATIC Drive Controller family (All versions < V2.9.2), SIMATIC ET 200SP Open…
CVE-2023-46156 — High (CVSS 7.5): Affected devices improperly handle specially crafted packets sent to port 102/tcp. This could allow an attacker to…
CVE-2023-28831 — High (CVSS 7.5): The OPC UA implementations (ANSI C and C++) in affected products contain an integer overflow vulnerability that could…
CVE-2021-40365 — High (CVSS 7.5): Affected devices don't process correctly certain special crafted packets sent to port 102/tcp, which could allow an…
CVE-2021-37205 — High (CVSS 7.5): A vulnerability has been identified in SIMATIC Drive Controller family (All versions >= V2.9.2 < V2.9.4), SIMATIC ET…
CVE-2021-37204 — High (CVSS 7.5): A vulnerability has been identified in SIMATIC Drive Controller family (All versions < V2.9.2), SIMATIC Drive…

All CVEs affecting Siemens Simatic S7-plcsim Advanced Firmware →

Other CWE-1286 vulnerabilities

CVE-2025-41719 — High (CVSS 8.8): A low privileged remote attacker can corrupt the webserver users storage on the device by setting a sequence of…
CVE-2026-6442 — High (CVSS 8.3): Improper validation of bash commands in Snowflake Cortex Code CLI versions prior to 1.0.25 allowed subsequent commands…
CVE-2024-26507 — High (CVSS 7.8): An issue in FinalWire AIRDA Extreme, AIDA64 Engineer, AIDA64 Business, AIDA64 Network Audit v.7.00.6700 and before…
CVE-2025-8873 — High (CVSS 7.5): On affected platforms running Arista EOS with IPsec configured, a specially crafted packet can cause the dataplane to…
CVE-2026-7307 — High (CVSS 7.5): A flaw was found in Keycloak. A remote, unauthenticated attacker can send a specially crafted XML input to the Security…
CVE-2026-40198 — High (CVSS 7.5): Net::CIDR::Lite versions before 0.23 for Perl does not validate IPv6 group count, which may allow IP ACL…

Browse all CWE-1286 vulnerabilities →