CVE-2020-27736
Siemens · published 2021-04-22
Source record Collected from the National Vulnerability Database (NVD)
Description
Description by Siemens AG via the CVE Program.
A vulnerability has been identified in APOGEE PXC Compact (BACnet) (All versions < V3.5.5), APOGEE PXC Compact (P2 Ethernet) (All versions < V2.8.20), APOGEE PXC Modular (BACnet) (All versions < V3.5.5), APOGEE PXC Modular (P2 Ethernet) (All versions < V2.8.20), Nucleus NET (All versions), Nucleus ReadyStart V3 (All versions < V2017.02.3), Nucleus ReadyStart V4 (All versions < V4.1.0), Nucleus Source Code (Versions including affected DNS modules), SIMOTICS CONNECT 400 (All versions < V0.5.0.0), TALON TC Compact (BACnet) (All versions < V3.5.5), TALON TC Modular (BACnet) (All versions < V3.5.5). The DNS domain name label parsing functionality does not properly validate the null-terminated name in DNS-responses. The parsing of malformed responses could result in a read past the end of an allocated structure. An attacker with a privileged position in the network could leverage this vulnerability to cause a denial-of-service condition or leak the read memory.
Status at the source
- NVD status: Modified
Affected products, as the source lists them
| Vendor | Product | Versions |
|---|---|---|
| Siemens | APOGEE PXC Compact (BACnet) | All versions < V3.5.5: affected |
| Siemens | APOGEE PXC Compact (P2 Ethernet) | All versions < V2.8.20: affected |
| Siemens | APOGEE PXC Modular (BACnet) | All versions < V3.5.5: affected |
| Siemens | APOGEE PXC Modular (P2 Ethernet) | All versions < V2.8.20: affected |
| Siemens | Nucleus NET | All versions: affected |
| Siemens | Nucleus ReadyStart V3 | All versions < V2017.02.3: affected |
| Siemens | Nucleus ReadyStart V4 | All versions < V4.1.0: affected |
| Siemens | Nucleus Source Code | Versions including affected DNS modules: affected |
| Siemens | SIMOTICS CONNECT 400 | All versions < V0.5.0.0: affected |
| Siemens | TALON TC Compact (BACnet) | All versions < V3.5.5: affected |
| Siemens | TALON TC Modular (BACnet) | All versions < V3.5.5: affected |
Products named in NVD's CPE match criteria (5)
cpe:2.3:a:siemens:nucleus_net:*:*:*:*:*:*:*:*cpe:2.3:a:siemens:nucleus_readystart_v3:*:*:*:*:*:*:*:*cpe:2.3:a:siemens:nucleus_readystart_v4:*:*:*:*:*:*:*:*cpe:2.3:a:siemens:nucleus_source_code:-:*:*:*:*:*:*:*cpe:2.3:o:siemens:simotics_connect_400_firmware:*:*:*:*:*:*:*:*
DeSpy has not checked any unit, hardware revision or firmware. A product missing here is not a statement that it is unaffected.
Scores, as their sources published them
- CVSS 3.1: 6.5 MEDIUM — as published by Siemens AG (Secondary)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H - CVSS 3.1: 6.5 MEDIUM — as published by NIST (Primary)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H - CVSS 2.0: 5.8 MEDIUM — as published by NIST (Primary)
AV:N/AC:M/Au:N/C:P/I:N/A:P
DeSpy does not score records. These are the sources' own values.
Weaknesses
Sources
References the source lists
- https://cert-portal.siemens.com/productcert/pdf/ssa-180579.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-669158.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-705111.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-180579.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-669158.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-705111.pdf
Source dates: published 2021-04-22, last changed 2026-06-17. DeSpy's copy of this version is dated 2026-09-28.
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