Detections
Analytics

Siemens Web Server of SCALANCE X200 Heap-Based Buffer Overflow (CVE-2021-25668)

critical Tenable OT Security Plugin ID 500764

Synopsis

The remote OT asset is affected by a vulnerability.

Description

A vulnerability has been identified in SCALANCE X200-4P IRT (All versions < 5.5.1), SCALANCE X201-3P IRT (All versions < 5.5.1), SCALANCE X201-3P IRT PRO (All versions < 5.5.1), SCALANCE X202-2 IRT (All versions < 5.5.1), SCALANCE X202-2P IRT (incl. SIPLUS NET variant) (All versions < 5.5.1), SCALANCE X202-2P IRT PRO (All versions < 5.5.1), SCALANCE X204 IRT (All versions < 5.5.1), SCALANCE X204 IRT PRO (All versions < 5.5.1), SCALANCE X204-2 (incl. SIPLUS NET variant) (All versions < V5.2.5), SCALANCE X204-2FM (All versions < V5.2.5), SCALANCE X204-2LD (incl. SIPLUS NET variant) (All versions < V5.2.5), SCALANCE X204-2LD TS (All versions < V5.2.5), SCALANCE X204-2TS (All versions < V5.2.5), SCALANCE X206-1 (All versions < V5.2.5), SCALANCE X206-1LD (All versions < V5.2.5), SCALANCE X208 (incl. SIPLUS NET variant) (All versions < V5.2.5), SCALANCE X208PRO (All versions < V5.2.5), SCALANCE X212-2 (incl. SIPLUS NET variant) (All versions < V5.2.5), SCALANCE X212-2LD (All versions < V5.2.5), SCALANCE X216 (All versions < V5.2.5), SCALANCE X224 (All versions < V5.2.5), SCALANCE XF201-3P IRT (All versions < 5.5.1), SCALANCE XF202-2P IRT (All versions < 5.5.1), SCALANCE XF204 (All versions < V5.2.5), SCALANCE XF204 IRT (All versions < 5.5.1), SCALANCE XF204-2 (incl. SIPLUS NET variant) (All versions < V5.2.5), SCALANCE XF204-2BA IRT (All versions < 5.5.1), SCALANCE XF206-1 (All versions < V5.2.5), SCALANCE XF208 (All versions < V5.2.5). Incorrect processing of POST requests in the webserver may result in write out of bounds in heap.
An attacker might leverage this to cause denial-of-service on the device and potentially remotely execute code.

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

Solution

The following text was originally created by the Cybersecurity and Infrastructure Security Agency (CISA). The original can be found at CISA.gov.

Siemens recommends upgrading the following products to v5.5.1:

- SCALANCE X200-4P IRT
- SCALANCE X201-3P IRT
- SCALANCE X201-3P IRT PRO
- SCALANCE X202-2 IRT
- SCALANCE X202-2P IRT (incl. SIPLUS NET variant)
- SCALANCE X202-2P IRT PRO
- SCALANCE X204 IRT
- SCALANCE X204 IRT PRO
- SCALANCE XF201-3P IRT
- SCALANCE XF202-2P IRT
- SCALANCE XF204 IRT
- SCALANCE XF204-2BA IRT

Siemens recommends upgrading the following products to v5.2.5 or later:

- SCALANCE X204-2 (incl. SIPLUS NET variant)
- SCALANCE X204-2FM
- SCALANCE X204-2LD (incl. SIPLUS NET variant) SCALANCE X204-2LD TS
- SCALANCE X204-2TS
- SCALANCE X206-1
- SCALANCE X206-1LD
- SCALANCE X208 (incl. SIPLUS NET variant)
- SCALANCE X208PRO
- SCALANCE X212-2 (incl. SIPLUS NET variant)
- SCALANCE X212-2LD
- SCALANCE X216
- SCALANCE X224
- SCALANCE XF204
- SCALANCE XF204-2 (incl. SIPLUS NET variant)
- SCALANCE XF206-1
- SCALANCE XF208

Siemens has identified the following specific workarounds and mitigations users can apply to reduce the risk:

- Limit network traffic of web servers of Scalance X switches to trusted connections by firewall rules (Ports 443/TCP and 80/TCP).

As a general security measure, Siemens strongly recommends protecting network access to devices with appropriate mechanisms. In order to operate the devices in a protected IT environment, Siemens recommends configuring the environment according to Siemens operational guidelines for Industrial Security and following the recommendations in the product manuals.

For additional information, please refer to Siemens Security Advisory SSA-187092

See Also

https://cert-portal.siemens.com/productcert/pdf/ssa-187092.pdf

https://www.cisa.gov/news-events/ics-advisories/icsa-21-103-07

Plugin Details

Severity: Critical

ID: 500764

Version: 1.9

Type: remote

Family: Tenable.ot

Published: 1/25/2023

Updated: 11/25/2024

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 5.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS Score Source: CVE-2021-25668

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

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

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:siemens:scalance_x202-2_irt_firmware, cpe:/o:siemens:scalance_xf202-2p_irt_firmware, cpe:/o:siemens:scalance_x204-2ld_ts_firmware, cpe:/o:siemens:scalance_x224_firmware, cpe:/o:siemens:scalance_xf204-2ba_irt_firmware, cpe:/o:siemens:scalance_x206-1_firmware, cpe:/o:siemens:scalance_xf206-1_firmware, cpe:/o:siemens:scalance_x204-2ts_firmware, cpe:/o:siemens:scalance_x206-1ld_firmware, cpe:/o:siemens:scalance_x204-2_firmware, cpe:/o:siemens:scalance_x204-2ld_firmware, cpe:/o:siemens:scalance_x204-2fm_firmware, cpe:/o:siemens:scalance_x201-3p_irt_pro_firmware, cpe:/o:siemens:scalance_xf201-3p_irt_firmware, cpe:/o:siemens:scalance_x208_firmware, cpe:/o:siemens:scalance_x201-3p_irt_firmware, cpe:/o:siemens:scalance_xf204-2_firmware, cpe:/o:siemens:scalance_x202-2p_irt_pro_firmware, cpe:/o:siemens:scalance_x204_irt_firmware, cpe:/o:siemens:scalance_xf204_irt_firmware, cpe:/o:siemens:scalance_x212-2ld_firmware, cpe:/o:siemens:scalance_x204_irt_pro_firmware, cpe:/o:siemens:scalance_x212-2_firmware, cpe:/o:siemens:scalance_x202-2p_irt_firmware, cpe:/o:siemens:scalance_x208pro_firmware, cpe:/o:siemens:scalance_xf208_firmware, cpe:/o:siemens:scalance_x200-4p_irt_firmware, cpe:/o:siemens:scalance_xf204_firmware, cpe:/o:siemens:scalance_x216_firmware

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 4/22/2021

Vulnerability Publication Date: 4/22/2021

Reference Information

CVE: CVE-2021-25668

CWE: 122, 787

ICSA: 21-103-07