Out-of-bounds Read in Siemens Apogee Pxc Compact (Bacnet)
CVE-2020-27736
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H.
EPSS exploit prediction
EPSS: 0.036 (89.2th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 89th percentile — 89.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.036 · newest: 0.036 · change: 0.000
Affected products
- Siemens Apogee Pxc Compact (Bacnet) — versions All versions < V3.5.5
- Siemens Apogee Pxc Compact (P2 Ethernet) — versions All versions < V2.8.20
- Siemens Apogee Pxc Modular (Bacnet) — versions All versions < V3.5.5
- Siemens Apogee Pxc Modular (P2 Ethernet) — versions All versions < V2.8.20
- Siemens Nucleus Net — versions All versions
- Siemens Nucleus Net
- Siemens Nucleus Readystart V3 — versions All versions < V2017.02.3
- Siemens Nucleus Readystart V3
- Siemens Nucleus Readystart V4 — versions All versions < V4.1.0
- Siemens Nucleus Readystart V4
Weakness classification (CWE)
References
- cert-portal.siemens.com/productcert/pdf/ssa-705111.pdf (Patch, Vendor Advisory)
- cert-portal.siemens.com/productcert/pdf/ssa-669158.pdf (Patch, Vendor Advisory)
- cert-portal.siemens.com/productcert/pdf/ssa-180579.pdf
Frequently asked questions
- What is CVE-2020-27736?
- CVE-2020-27736 is a medium-severity vulnerability in Siemens Apogee Pxc Compact (Bacnet), classified under Improper Null Termination. CVSS score: 6.5/10. Published 2021-04-22.
- How severe is CVE-2020-27736?
- Medium severity. CVSS v3 base score is 6.5 out of 10.