Siemens RUGGEDCOM RST2428P Permissive Regular Expression (CVE-2025-40271)

high Tenable OT Security Plugin ID 505403

Synopsis

The remote OT asset is affected by a vulnerability.

Description

In the Linux kernel, the following vulnerability has been resolved:
fs/proc: fix uaf in proc_readdir_de() Pde is erased from subdir rbtree through rb_erase(), but not set the node to EMPTY, which may result in uaf access. We should use RB_CLEAR_NODE() set the erased node to EMPTY, then pde_subdir_next() will return NULL to avoid uaf access. We found an uaf issue while using stress-ng testing, need to run testcase getdent and tun in the same time. The steps of the issue is as follows: 1) use getdent to traverse dir /proc/pid/net/dev_snmp6/, and current pde is tun3; 2) in the [time windows] unregister netdevice tun3 and tun2, and erase them from rbtree. erase tun3 first, and then erase tun2. the pde(tun2) will be released to slab; 3) continue to getdent process, then pde_subdir_next() will return pde(tun2) which is released, it will case uaf access. CPU 0 | CPU 1 --------------------------------------------------------------------
----- traverse dir /proc/pid/net/dev_snmp6/ | unregister_netdevice(tun->dev) //tun3 tun2 sys_getdents64() | iterate_dir() | proc_readdir() | proc_readdir_de() | snmp6_unregister_dev() pde_get(de); | proc_remove() read_unlock(&proc_subdir_lock); | remove_proc_subtree() | write_lock(&proc_subdir_lock); [time window] | rb_erase(&root->subdir_node, &parent->subdir);
| write_unlock(&proc_subdir_lock);
read_lock(&proc_subdir_lock); | next = pde_subdir_next(de); | pde_put(de);
| de = next; //UAF | rbtree of dev_snmp6 | pde(tun3) / \ NULL pde(tun2)

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Please visit https://www.tenable.com/products/tenable-ot for more information.

Solution

Refer to the vendor advisory.

Plugin Details

Severity: High

ID: 505403

File Name: tenable_ot_siemens_CVE-2025-40271.nasl

Version: 1.1

Type: Remote

Family: Tenable.ot

Published: 6/18/2026

Updated: 6/18/2026

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: High

Score: 7.4

CVSS v3

Risk Factor: High

Base Score: 7

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

Vulnerability Information

CPE: cpe:/o:siemens:ruggedcom_rst2428p_firmware

Required KB Items: Tenable.ot/Siemens

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 6/2/2026

Vulnerability Publication Date: 12/6/2025

Reference Information

CVE: CVE-2025-40271

CWE: 625

Detections

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