Critical severity · published Sep 14, 2021
CVE-2021-27391
A vulnerability has been identified in APOGEE MBC (PPC) (P2 Ethernet) (All versions >= V2.6.3), APOGEE MEC (PPC) (P2 Ethernet) (All versions >= V2.6.3), APOGEE PXC Compact…
9.8
CVSS
3.4%
EPSS
No
On KEV
Description
A vulnerability has been identified in APOGEE MBC (PPC) (P2 Ethernet) (All versions >= V2.6.3), APOGEE MEC (PPC) (P2 Ethernet) (All versions >= V2.6.3), APOGEE PXC Compact (BACnet) (All versions < V3.5.3), APOGEE PXC Compact (P2 Ethernet) (All versions >= V2.8), APOGEE PXC Modular (BACnet) (All versions < V3.5.3), APOGEE PXC Modular (P2 Ethernet) (All versions >= V2.8), TALON TC Compact (BACnet) (All versions < V3.5.3), TALON TC Modular (BACnet) (All versions < V3.5.3). The web server of affected devices lacks proper bounds checking when parsing the Host parameter in HTTP requests, which could lead to a buffer overflow. An unauthenticated remote attacker could exploit this vulnerability to execute arbitrary code on the device with root privileges.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.4% · higher than 89% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AM
APOGEE MBC (PPC) (P2 Ethernet) · Siemens
All versions >= V2.6.3 · source: vendor
AM
APOGEE MEC (PPC) (P2 Ethernet) · Siemens
All versions >= V2.6.3 · source: vendor
AP
APOGEE PXC Compact (BACnet) · Siemens
All versions < V3.5.3 · source: vendor
AP
APOGEE PXC Compact (P2 Ethernet) · Siemens
All versions >= V2.8 · source: vendor
AP
APOGEE PXC Modular (BACnet) · Siemens
All versions < V3.5.3 · source: vendor
AP
APOGEE PXC Modular (P2 Ethernet) · Siemens
All versions >= V2.8 · source: vendor
TT
TALON TC Compact (BACnet) · Siemens
All versions < V3.5.3 · source: vendor
TT
TALON TC Modular (BACnet) · Siemens
All versions < V3.5.3 · source: vendor
AM
Apogee Mbc (ppc) (p2 Ethernet) Firmware · Siemens
through 2.6.3 · source: NVD
AM
Apogee Mec (ppc) (p2 Ethernet) Firmware · Siemens
through 2.6.3 · source: NVD
AP
Apogee Pxc Bacnet Automation Controller Firmware · Siemens
before 3.5.3 · source: NVD
AP
Apogee Pxc Compact (p2 Ethernet) Firmware · Siemens
through 2.8 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-27391
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-27391
Patch
https://cert-portal.siemens.com/productcert/pdf/ssa-944498.pdf
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