What is the CVSS score of CVE-2021-27391?

CVE-2021-27391 has a CVSS 3.1 base score of 9.8 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 3.4%.

Is there a patch available for CVE-2021-27391?

Yes, a patch is available for CVE-2021-27391. Update the affected software to the latest version immediately.

Apogee Mbc Ppc P2 Ethernet Firmware CVE-2021-27391

CRITICAL

Classic Buffer Overflow (CWE-120)

2021-09-14 productcert@siemens.com

Buffer Overflow RCE Apogee Mbc Ppc P2 Ethernet Firmware Apogee Mec Ppc P2 Ethernet Firmware Apogee Pxc Bacnet Automation Controller Firmware Apogee Pxc Compact P2 Ethernet Firmware Apogee Pxc Modular Bacnet Firmware Apogee Pxc Modular P2 Ethernet Firmware Talon Tc Compact Bacnet Firmware Talon Tc Modular Bacnet Firmware

9.8

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

9.8 CRITICAL

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

CVE Published

Sep 14, 2021 - 11:15 nvd

CRITICAL 9.8

DescriptionNVD

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.

AnalysisAI

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 <. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Buffer Copy without Size Check vulnerability could allow attackers to overflow a buffer to corrupt adjacent memory.

Technical ContextAI

This vulnerability is classified as Buffer Copy without Size Check (CWE-120), which allows attackers to overflow a buffer to corrupt adjacent memory. 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. Affected products include: Siemens Apogee Mbc \(Ppc\) \(P2 Ethernet\) Firmware, Siemens Apogee Mec \(Ppc\) \(P2 Ethernet\) Firmware, Siemens Apogee Pxc Bacnet Automation Controller Firmware, Siemens Apogee Pxc Compact \(P2 Ethernet\) Firmware, Siemens Apogee Pxc Modular \(Bacnet\) Firmware.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Always validate buffer sizes before copy operations. Use bounded functions (strncpy, snprintf). Enable compiler protections.