CVE-2020-17437
mediumpriority · track · 34stack campaign · AMNESIA:33EPSS 0.028 · 86 %ileDEEURUUSEPSS · scored 2026-10-27
An issue was discovered in uIP 1.0, as used in Contiki 3.0 and other products. When the Urgent flag is set in a TCP packet, and the stack is configured to ignore the urgent data, the stack attempts to use the value of the Urgent pointer bytes to separate the Urgent data from the normal data, by calculating the offset at which the normal data should be present in the global buffer. However, the length of this offset is not checked; therefore, for large values of the Urgent pointer bytes, the data pointer can point to memory that is way beyond the data buffer in uip_process in uip.c.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedSENTRON 3VA COM100/800siemens_psirt
Update to V4.4.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109765343/ - FixedSENTRON 3VA DSP800siemens_psirt
Update to V4.0 or later version
https://support.industry.siemens.com/cs/ww/en/view/109799046/ - FixedSENTRON PAC2200 (with MID Approval)siemens_psirt
MID-certified devices do not support firmware updates; V3.2.2 is contained in devices that are labeled as "M22 MID"
- FixedSENTRON PAC2200 (without MID Approval)siemens_psirt
Update to V3.2.2 or later version
https://support.industry.siemens.com/cs/ww/en/view/109760897/ - FixedSENTRON PAC3200siemens_psirt
Update to V2.4.7 or later version
https://support.industry.siemens.com/cs/ww/en/view/31674577/ - FixedSENTRON PAC3200Tsiemens_psirt
Update to V3.2.2 or later version
https://support.industry.siemens.com/cs/ww/en/view/109793060/ - FixedSENTRON PAC3220siemens_psirt
Update to V3.2.0 or later version
https://support.industry.siemens.com/cs/ww/en/view/109780938/ - FixedSENTRON PAC4200siemens_psirt
Update to V2.3.0 or later version
https://support.industry.siemens.com/cs/ww/en/view/35029840/ - FixedFNETcisa_csaf_ot
Additional vendors affected by the reported vulnerabilities have also released security advisories related to their affected products. Those advisories are as follows:
https://yanzi.dev/#/security/advisories/2020-12-08 - FixedNut/Netcisa_csaf_ot
Additional vendors affected by the reported vulnerabilities have also released security advisories related to their affected products. Those advisories are as follows:
https://yanzi.dev/#/security/advisories/2020-12-08 - Fixedopen-iscsicisa_csaf_ot
Additional vendors affected by the reported vulnerabilities have also released security advisories related to their affected products. Those advisories are as follows:
https://yanzi.dev/#/security/advisories/2020-12-08 - FixedpicoTCP (EOL)cisa_csaf_ot
Additional vendors affected by the reported vulnerabilities have also released security advisories related to their affected products. Those advisories are as follows:
https://yanzi.dev/#/security/advisories/2020-12-08 - FixedpicoTCP-NGcisa_csaf_ot
Additional vendors affected by the reported vulnerabilities have also released security advisories related to their affected products. Those advisories are as follows:
https://yanzi.dev/#/security/advisories/2020-12-08 - FixeduIP (EOL)cisa_csaf_ot
Additional vendors affected by the reported vulnerabilities have also released security advisories related to their affected products. Those advisories are as follows:
https://yanzi.dev/#/security/advisories/2020-12-08 - FixeduIP-Contiki-NGcisa_csaf_ot
Additional vendors affected by the reported vulnerabilities have also released security advisories related to their affected products. Those advisories are as follows:
https://yanzi.dev/#/security/advisories/2020-12-08 - FixeduIP-Contiki-OS (end-of-life [EOL])cisa_csaf_ot
Additional vendors affected by the reported vulnerabilities have also released security advisories related to their affected products. Those advisories are as follows:
https://yanzi.dev/#/security/advisories/2020-12-08 - FixedSENTRON 3VA COM100/800cisa_csaf_ot
Update to V4.4.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109765343/ - FixedSENTRON 3VA DSP800cisa_csaf_ot
Update to V4.0 or later version
https://support.industry.siemens.com/cs/ww/en/view/109799046/ - FixedSENTRON PAC2200 (with MID Approval)cisa_csaf_ot
MID-certified devices do not support firmware updates; V3.2.2 is contained in devices that are labeled as "M22 MID"
- FixedSENTRON PAC2200 (without MID Approval)cisa_csaf_ot
Update to V3.2.2 or later version
https://support.industry.siemens.com/cs/ww/en/view/109760897/ - FixedSENTRON PAC3200cisa_csaf_ot
Update to V2.4.7 or later version
https://support.industry.siemens.com/cs/ww/en/view/31674577/ - FixedSENTRON PAC3200Tcisa_csaf_ot
Update to V3.2.2 or later version
https://support.industry.siemens.com/cs/ww/en/view/109793060/ - FixedSENTRON PAC3220cisa_csaf_ot
Update to V3.2.0 or later version
https://support.industry.siemens.com/cs/ww/en/view/109780938/ - FixedSENTRON PAC4200cisa_csaf_ot
Update to V2.3.0 or later version
https://support.industry.siemens.com/cs/ww/en/view/35029840/ - MitigationSENTRON 3VA COM100/800siemens_psirt
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON 3VA DSP800siemens_psirt
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON PAC2200 (with CLP Approval)siemens_psirt
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON PAC2200 (with MID Approval)siemens_psirt
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON PAC2200 (without MID Approval)siemens_psirt
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON PAC3200siemens_psirt
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON PAC3200Tsiemens_psirt
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON PAC3220siemens_psirt
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON PAC4200siemens_psirt
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON 3VA COM100/800cisa_csaf_ot
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON 3VA DSP800cisa_csaf_ot
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON PAC2200 (with CLP Approval)cisa_csaf_ot
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON PAC2200 (with MID Approval)cisa_csaf_ot
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON PAC2200 (without MID Approval)cisa_csaf_ot
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON PAC3200cisa_csaf_ot
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON PAC3200Tcisa_csaf_ot
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON PAC3220cisa_csaf_ot
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- MitigationSENTRON PAC4200cisa_csaf_ot
For successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
- No fix plannedSENTRON PAC2200 (with CLP Approval)siemens_psirt
Currently no remediation is planned
- No fix plannedSENTRON PAC2200 (with CLP Approval)cisa_csaf_ot
Currently no remediation is planned
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.4–8.2
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (56)
Products and version ranges known to be affected.
- Unify OpenScape Common Management Platformall versionscert_bundDEcpe:/a:unify:openscape_common_management_platform:-
advisories (4)
Vendor and ecosystem advisories describing this.
- SSA-541018SSA-541018: Embedded TCP/IP Stack Vulnerabilities (AMNESIA:33) in SENTRON PAC / 3VA Devices (Part 2)2021-03-09csaf · siemens_psirtDE
Security researchers discovered and disclosed 33 vulnerabilities in several open-source TCP/IP stacks for embedded devices, also known as "AMNESIA:33" vulnerabilities. This advisory describes the impact of two of these vulnerabilities (CVE-2020-13987, CVE-2020-17437) to Siemens products. Siemens has released updates for several affected products and recommends to update to the latest versions. Siemens recommends specific countermeasures for products where updates are not available. The impact of another "AMNESIA:33" vulnerability (CVE-2020-13988) is described in Siemens Security Advisory SSA-541017.
- WID-SEC-W-2022-1044TCP/IP Stack: Mehrere SchwachstellenDeutsch2020-12-08csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in TCP/IP Stack ausnutzen, um beliebigen Programmcode mit Administratorrechten auszuführen, einen Denial of Service Angriff durchzuführen, vertrauliche Daten einzusehen oder Daten zu manipulieren.
- ICSA-20-343-01Multiple Embedded TCP/IP Stacks2020-12-08icsa · cisa_csaf_otUS
Successful exploitation of these vulnerabilities could allow attackers to corrupt memory, put devices into infinite loops, access unauthorized data, and/or poison DNS cache.
- ICSA-21-068-06Siemens TCP/IP Stack Vulnerabilities-AMNESIA:33 in SENTRON PAC / 3VA Devices (Update C)2021-03-09icsa · cisa_csaf_otUS
Security researchers discovered and disclosed 33 vulnerabilities in several open-source TCP/IP stacks for embedded devices, also known as "AMNESIA:33" vulnerabilities. This advisory describes the impact of two of these vulnerabilities (CVE-2020-13987, CVE-2020-17437) to Siemens products. Siemens has released updates for several affected products and recommends to update to the latest versions. Siemens recommends specific countermeasures for products where updates are not available. The impact of another "AMNESIA:33" vulnerability (CVE-2020-13988) is described in Siemens Security Advisory SSA-541017.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (18)
External citations — patches, advisories, analysis.
- https://cert-portal.siemens.com/productcert/pdf/ssa-541018.pdfcnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2020-17437cnnvd
- https://us-cert.cisa.gov/ics/advisories/icsa-20-343-01cnnvd
- https://us-cert.cisa.gov/ics/advisories/icsa-21-068-06cnnvd
- https://vigilance.fr/vulnerability/uIP-out-of-bounds-memory-reading-via-uip-process-34721cnnvd
- https://www.auscert.org.au/bulletins/ESB-2020.4363/cnnvd
- https://www.auscert.org.au/bulletins/ESB-2021.0767cnnvd
- https://www.auscert.org.au/bulletins/ESB-2021.1235cnnvd
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