Siemens SCALANCE W700 Double Free (CVE-2023-29469)

medium Tenable OT Security Plugin ID 502869

Synopsis

The remote OT asset is affected by a vulnerability.

Description

An issue was discovered in libxml2 before 2.10.4. When hashing empty dict strings in a crafted XML document, xmlDictComputeFastKey in dict.c can produce non-deterministic values, leading to various logic and memory errors, such as a double free. This behavior occurs because there is an attempt to use the first byte of an empty string, and any value is possible (not solely the '\0' value).

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

- All affected products: Update to V3.0.0 or later version

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

Additional information on industrial security by Siemens can be found on the Siemens industrial security webpage

For more information see the associated Siemens security advisory SSA-769027 in HTML and CSAF.

See Also

https://cert-portal.siemens.com/productcert/html/ssa-398330.html

https://cert-portal.siemens.com/productcert/pdf/ssa-556635.pdf

https://cert-portal.siemens.com/productcert/pdf/ssa-625862.pdf

https://cert-portal.siemens.com/productcert/pdf/ssa-341067.pdf

https://cert-portal.siemens.com/productcert/html/ssa-769027.html

https://support.industry.siemens.com/cs/ww/en/view/109955177/

https://support.industry.siemens.com/cs/ww/en/view/109955597/

https://support.industry.siemens.com/cs/ww/en/view/109977720/

https://support.industry.siemens.com/cs/ww/en/view/109954475/

https://www.cisa.gov/news-events/ics-advisories/icsa-25-044-09

Plugin Details

Severity: Medium

ID: 502869

File Name: tenable_ot_siemens_CVE-2023-29469.nasl

Version: 1.4

Type: remote

Family: Tenable.ot

Published: 2/24/2025

Updated: 2/14/2026

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

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

CVSS Score Source: CVE-2023-29469

CVSS v3

Risk Factor: Medium

Base Score: 6.5

Temporal Score: 5.7

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

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

Vulnerability Information

CPE: cpe:/o:siemens:scalance_wam763-1_%28us%29_firmware:3.0.0, cpe:/o:siemens:scalance_wam763-1_firmware:3.0.0, cpe:/o:siemens:scalance_wam766-1_%28us%29_firmware:3.0.0, cpe:/o:siemens:scalance_wam766-1_firmware:3.0.0, cpe:/o:siemens:scalance_wam766-1_eec_%28us%29_firmware:3.0.0, cpe:/o:siemens:simatic_cp_1542sp-1_irc_firmware:2.3, cpe:/o:siemens:scalance_wum766-1_firmware:3.0.0, cpe:/o:siemens:scalance_wam766-1_%28me%29_firmware:3.0.0, cpe:/o:siemens:scalance_wum763-1_firmware:3.0.0, cpe:/o:siemens:scalance_wub762-1_ifeatures_firmware:3.0.0, cpe:/o:siemens:scalance_wam766-1_eec_%28me%29_firmware:3.0.0, cpe:/o:siemens:simatic_s7-1500_cpu_firmware:3.1.5, cpe:/o:siemens:scalance_wab762-1_firmware:3.0.0, cpe:/o:siemens:scalance_wam766-1_eec_firmware:3.0.0, cpe:/o:siemens:siplus_et_200sp_cp_1543sp-1_isec_tx_rail_firmware:2.3, cpe:/o:siemens:siplus_et_200sp_cp_1543sp-1_isec_firmware:2.3, cpe:/o:siemens:simatic_cp_1542sp-1_firmware:2.3, cpe:/o:siemens:scalance_wub762-1_firmware:3.0.0, cpe:/o:siemens:scalance_wam763-1_%28me%29_firmware:3.0.0, cpe:/o:siemens:scalance_wum766-1_%28usa%29_firmware:3.0.0, cpe:/o:siemens:scalance_wum766-1_%28me%29_firmware:3.0.0, cpe:/o:siemens:siplus_et_200sp_cp_1542sp-1_irc_tx_rail_firmware:2.3, cpe:/o:siemens:simatic_cp_1543sp-1_firmware:2.3, cpe:/o:siemens:siplus_s7-1500_cpu_firmware:3.1.5, cpe:/o:siemens:scalance_wum763-1_%28us%29_firmware:3.0.0

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 12/12/2023

Vulnerability Publication Date: 12/12/2023

Reference Information

CVE: CVE-2023-29469

CWE: 415

ICSA: 25-044-09