SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-31889

A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All versions), Capital Embedded AR Classic R20-11 (All versions < V2303), PLUSCONTROL 1st Gen (All versions), SIMOTICS CONNECT 400 (All versions < V0.5.0.0).

CRITICAL 9.1EPSS 2.17%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (2.17%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All versions), Capital Embedded AR Classic R20-11 (All versions < V2303), PLUSCONTROL 1st Gen (All versions), SIMOTICS CONNECT 400 (All versions < V0.5.0.0). Malformed TCP packets with a corrupted SACK option leads to Information Leaks and Denial-of-Service conditions. (FSMD-2021-0015)

CVSS 3.1
9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
EPSS
2.17% probability · 81th percentile
CISA KEV
Not listed
Weakness
CWE-191
Affected
siemens/capital vstar · siemens/nucleus net · siemens/nucleus readystart v3 · siemens/nucleus source code · siemens/apogee modular building controller firmware · siemens/apogee modular equiment controller firmware · siemens/apogee pxc compact firmware · siemens/apogee pxc modular firmware · siemens/talon tc compact firmware · siemens/talon tc modular firmware
Source
productcert@siemens.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.