CVE-2021-27391

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.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 2.86% Top 15%
Vendor Advisory siemens.com
Affected: Siemens APOGEE MBC (PPC) (P2 Ethernet)
Affected: Siemens APOGEE MEC (PPC) (P2 Ethernet)
Affected: Siemens APOGEE PXC Compact (BACnet)
Affected: Siemens APOGEE PXC Compact (P2 Ethernet)
Affected: Siemens APOGEE PXC Modular (BACnet)
Affected: Siemens APOGEE PXC Modular (P2 Ethernet)
Affected: Siemens TALON TC Compact (BACnet)
Affected: Siemens TALON TC Modular (BACnet)
Published at:
Updated at:

References

Link Tags
https://cert-portal.siemens.com/productcert/pdf/ssa-944498.pdf patch vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-27391?
CVE-2021-27391 has been scored as a critical severity vulnerability.
How to fix CVE-2021-27391?
To fix CVE-2021-27391, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-27391 being actively exploited in the wild?
It is possible that CVE-2021-27391 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~3% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-27391?
CVE-2021-27391 affects Siemens APOGEE MBC (PPC) (P2 Ethernet), Siemens APOGEE MEC (PPC) (P2 Ethernet), Siemens APOGEE PXC Compact (BACnet), Siemens APOGEE PXC Compact (P2 Ethernet), Siemens APOGEE PXC Modular (BACnet), Siemens APOGEE PXC Modular (P2 Ethernet), Siemens TALON TC Compact (BACnet), Siemens TALON TC Modular (BACnet).
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