peter bassill · operator
$ cve CVE-2021-31886 JSON

CVE-2021-31886

9.8
CRITICAL · CVSS 3.1 · EPSS 3% (pctl 87)

In your normal cycle

Critical by CVSS (9.8), but no sign of active exploitation.

Description

A vulnerability has been identified in APOGEE MBC (PPC) (BACnet) (All versions), APOGEE MBC (PPC) (P2 Ethernet) (All versions), APOGEE MEC (PPC) (BACnet) (All versions), APOGEE MEC (PPC) (P2 Ethernet) (All versions), APOGEE PXC Compact (BACnet) (All versions < V3.5.4), APOGEE PXC Compact (P2 Ethernet) (All versions < V2.8.19), APOGEE PXC Modular (BACnet) (All versions < V3.5.4), APOGEE PXC Modular (P2 Ethernet) (All versions < V2.8.19), Desigo PXC00-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC00-U (All versions >= V2.3 and < V6.30.016), Desigo PXC001-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC100-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC12-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC128-U (All versions >= V2.3 and < V6.30.016), Desigo PXC200-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC22-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC22.1-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC36.1-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC50-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC64-U (All versions >= V2.3 and < V6.30.016), Desigo PXM20-E (All versions >= V2.3 and < V6.30.016), Nucleus NET (All versions), Nucleus ReadyStart V3 (All versions < V2017.02.4), Nucleus Source Code (All versions), TALON TC Compact (BACnet) (All versions < V3.5.4), TALON TC Modular (BACnet) (All versions < V3.5.4). FTP server does not properly validate the length of the “USER” command, leading to stack-based buffer overflows. This may result in Denial-of-Service conditions and Remote Code Execution. (FSMD-2021-0010)

Scoring

CVSS9.8 (CRITICAL, v3.1)
VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS3.05% — more likely to be exploited than 87% of all CVEs
WeaknessCWE-170
On CISA KEVno
Public exploitnone known
Published2021-11-09
Last modified2026-06-17

Affected (40)

VendorProduct
siemensapogee modular building controller
siemensapogee modular building controller firmware
siemensapogee modular equiment controller
siemensapogee modular equiment controller firmware
siemensapogee pxc compact
siemensapogee pxc compact firmware
siemensapogee pxc modular
siemensapogee pxc modular firmware
siemensdesigo pxc00-e.d
siemensdesigo pxc00-e.d firmware
siemensdesigo pxc00-u
siemensdesigo pxc00-u firmware
siemensdesigo pxc001-e.d
siemensdesigo pxc001-e.d firmware
siemensdesigo pxc100-e.d
siemensdesigo pxc100-e.d firmware
siemensdesigo pxc12-e.d
siemensdesigo pxc12-e.d firmware
siemensdesigo pxc128-u
siemensdesigo pxc128-u firmware
siemensdesigo pxc200-e.d
siemensdesigo pxc200-e.d firmware
siemensdesigo pxc22-e.d
siemensdesigo pxc22-e.d firmware
siemensdesigo pxc22.1-e.d
siemensdesigo pxc22.1-e.d firmware
siemensdesigo pxc36.1-e.d
siemensdesigo pxc36.1-e.d firmware
siemensdesigo pxc50-e.d
siemensdesigo pxc50-e.d firmware
siemensdesigo pxc64-u
siemensdesigo pxc64-u firmware
siemensdesigo pxm20-e firmware
siemensnucleus net
siemensnucleus readystart v3
siemensnucleus source code
siemenstalon tc compact
siemenstalon tc compact firmware
siemenstalon tc modular
siemenstalon tc modular firmware

References

→ the Explorer  ·  watch your stack  ·  NVD