Siemens (CVE-2021-41991)

high Tenable.ot Plugin ID 500650

Synopsis

The remote OT asset is affected by a vulnerability.

Description

The in-memory certificate cache in strongSwan before 5.9.4 has a remote integer overflow upon receiving many requests with different certificates to fill the cache and later trigger the replacement of cache entries. The code attempts to select a less-often-used cache entry by means of a random number generator, but this is not done correctly. Remote code execution might be a slight possibility.

This plugin only works with Tenable.ot. Please visit https://www.tenable.com/products/tenable-ot for more information.

Solution

Refer to the vendor advisory.

See Also

http://www.nessus.org/u?845a2df0

https://github.com/strongswan/strongswan/releases/tag/5.9.4

https://www.debian.org/security/2021/dsa-4989

https://lists.debian.org/debian-lts-announce/2021/10/msg00014.html

http://www.nessus.org/u?cd6b6abd

http://www.nessus.org/u?ea295ec8

http://www.nessus.org/u?d5453363

https://cert-portal.siemens.com/productcert/pdf/ssa-539476.pdf

Plugin Details

Severity: High

ID: 500650

Version: 1.1

Type: remote

Family: Tenable.ot

Published: 4/28/2022

Updated: 4/28/2022

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: Medium

Base Score: 5

Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P

CVSS Score Source: CVE-2021-41991

CVSS v3

Risk Factor: High

Base Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Vulnerability Information

CPE: cpe:/o:siemens:siplus_et_200sp_cp_1542sp-1_irc_tx_rail_firmware:-, cpe:/o:siemens:siplus_et_200sp_cp_1543sp-1_isec_firmware:-, cpe:/o:siemens:siplus_et_200sp_cp_1543sp-1_isec_tx_rail_firmware:-, cpe:/o:siemens:siplus_s7-1200_cp_1243-1_firmware:-, cpe:/o:siemens:siplus_s7-1200_cp_1243-1_rail_firmware:-

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 10/18/2021

Vulnerability Publication Date: 10/18/2021

Reference Information

CVE: CVE-2021-41991