Integer underflow in Siemens Capital Embedded AR Classic 431-422
Priority MEDIUM 43CWE-191Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA.
Summary
A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All versions), Capital Embedded AR Classic R20-11 (All versions < V2303), PLUSCONTROL 1st Gen (All versions), SIMOTICS CONNECT 400 (All versions < V0.5.0.0). Malformed TCP packets with a corrupted SACK option leads to Information Leaks and Denial-of-Service conditions. (FSMD-2021-0015)
Why it matters now
EPSS 0.02175 82nd percentileScored 2026-11-07
Fix Fixed Capital Embedded AR Classic R20-11 (Siemens): V2303SIMOTICS CONNECT 400 (Siemens): V0.5.0.0
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Siemens | Capital Embedded AR Classic 431-422 | all versions | — | No fix listed | CNA |
| Siemens | Capital Embedded AR Classic R20-11 | before V2303 | V2303 | Patch available | CNA |
| Siemens | PLUSCONTROL 1st Gen | All versions | — | No fix listed | CNA |
| Siemens | SIMOTICS CONNECT 400 | before V0.5.0.0 | V0.5.0.0 | Patch available | CNA |
- Capital Embedded AR Classic 431-422 VendorSiemens Affected all versions Fixed in — No fix listed CNA
- Capital Embedded AR Classic R20-11 VendorSiemens Affected before V2303 Fixed in V2303 Patch available CNA
- PLUSCONTROL 1st Gen VendorSiemens Affected All versions Fixed in — No fix listed CNA
- SIMOTICS CONNECT 400 VendorSiemens Affected before V0.5.0.0 Fixed in V0.5.0.0 Patch available CNA
CPE configurations NVD · 16
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:siemens:capital_vstar:*:*:*:*:*:*:*:* | all versions | Vulnerable | Siemens |
| cpe:2.3:a:siemens:nucleus_net:*:*:*:*:*:*:*:* | all versions | Vulnerable | Siemens |
| cpe:2.3:a:siemens:nucleus_readystart_v3:*:*:*:*:*:*:*:* | before 2017.02.3 | Vulnerable | Siemens |
| cpe:2.3:a:siemens:nucleus_source_code:*:*:*:*:*:*:*:* | all versions | Vulnerable | Siemens |
| cpe:2.3:o:siemens:apogee_modular_building_controller_firmware:*:*:*:*:*:*:*:* | all versions | Vulnerable | Siemens |
| cpe:2.3:h:siemens:apogee_modular_building_controller:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Siemens |
| cpe:2.3:o:siemens:apogee_modular_equiment_controller_firmware:*:*:*:*:*:*:*:* | all versions | Vulnerable | Siemens |
| cpe:2.3:h:siemens:apogee_modular_equiment_controller:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Siemens |
| cpe:2.3:o:siemens:apogee_pxc_compact_firmware:*:*:*:*:*:*:*:* | all versions | Vulnerable | Siemens |
| cpe:2.3:h:siemens:apogee_pxc_compact:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Siemens |
- cpe:2.3:a:siemens:capital_vstar:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Siemens
- cpe:2.3:a:siemens:nucleus_net:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Siemens
- cpe:2.3:a:siemens:nucleus_readystart_v3:*:*:*:*:*:*:*:* Versions before 2017.02.3 Vulnerable ·Siemens
- cpe:2.3:a:siemens:nucleus_source_code:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Siemens
- cpe:2.3:o:siemens:apogee_modular_building_controller_firmware:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Siemens
- cpe:2.3:h:siemens:apogee_modular_building_controller:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Siemens
- cpe:2.3:o:siemens:apogee_modular_equiment_controller_firmware:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Siemens
- cpe:2.3:h:siemens:apogee_modular_equiment_controller:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Siemens
- cpe:2.3:o:siemens:apogee_pxc_compact_firmware:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Siemens
- cpe:2.3:h:siemens:apogee_pxc_compact:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Siemens
Show 6 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:siemens:apogee_pxc_modular_firmware:*:*:*:*:*:*:*:* | all versions | Vulnerable | Siemens |
| cpe:2.3:h:siemens:apogee_pxc_modular:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Siemens |
| cpe:2.3:o:siemens:talon_tc_compact_firmware:*:*:*:*:*:*:*:* | all versions | Vulnerable | Siemens |
| cpe:2.3:h:siemens:talon_tc_compact:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Siemens |
| cpe:2.3:o:siemens:talon_tc_modular_firmware:*:*:*:*:*:*:*:* | all versions | Vulnerable | Siemens |
| cpe:2.3:h:siemens:talon_tc_modular:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Siemens |
- cpe:2.3:o:siemens:apogee_pxc_modular_firmware:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Siemens
- cpe:2.3:h:siemens:apogee_pxc_modular:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Siemens
- cpe:2.3:o:siemens:talon_tc_compact_firmware:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Siemens
- cpe:2.3:h:siemens:talon_tc_compact:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Siemens
- cpe:2.3:o:siemens:talon_tc_modular_firmware:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Siemens
- cpe:2.3:h:siemens:talon_tc_modular:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Siemens
Remediation
- Fix · CNA Capital Embedded AR Classic R20-11 (Siemens) Fixed in V2303
- Fix · CNA SIMOTICS CONNECT 400 (Siemens) Fixed in V0.5.0.0
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
Siemens Capital Embedded AR Classic R20-11 V2303
8 records Highest priority Priority MEDIUM 4 MEDIUM, 4 LOW
Other records, highest priority first
- TI-2021-11879 A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All…Priority MEDIUM 44
- TI-2021-11490 A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All…Priority MEDIUM 43
- TI-2021-11489 A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All…Priority MEDIUM 43
Timeline
- 2026-10-02 Threatist record created from CVE-2021-31889
- 2026-10-03 Alias added: GHSA-9f8q-4pw9-8433
References
Advisory 2
Other 8
- https://cert-portal.siemens.com/productcert/pdf/ssa-620288.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-845392.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-223353.pdf
- https://cert-portal.siemens.com/productcert/html/ssa-114589.html
- https://cert-portal.siemens.com/productcert/html/ssa-044112.html
- https://cert-portal.siemens.com/productcert/html/ssa-620288.html
- https://cert-portal.siemens.com/productcert/html/ssa-845392.html
- https://cert-portal.siemens.com/productcert/html/ssa-223353.html
More Siemens Apogee Modular Building Controller Firmware vulnerabilities
- TI-2021-11875 Out-of-bounds write in Siemens APOGEE MBC CVSS 3.1CRITICAL 9.8
- TI-2022-17998 Uncontrolled resource consumption in Siemens APOGEE MBC CVSS 4.0HIGH 8.7
- TI-2021-11873 A vulnerability has been identified in APOGEE MBC (PPC) (BACnet) (All versions), APOGEE… CVSS 3.1CRITICAL 9.8
- TI-2021-11879 A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All… CVSS 3.1CRITICAL 9.1
- TI-2021-11877 Out-of-bounds write in Siemens APOGEE MBC CVSS 3.1HIGH 8.8
- TI-2021-11876 Out-of-bounds write in Siemens APOGEE MBC CVSS 3.1HIGH 8.8
Sources
- CVE-2021-31889 · CVE Program
- CVE-2021-31889 · NVD
- FIRST EPSS
- GHSA-9f8q-4pw9-8433 · GitHub Advisory Database · CC BY 4.0
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