Siemens SIMATIC S7-1500 TM MFP Improper Input Validation (CVE-2026-46307)

high Tenable OT Security Plugin ID 506380

Synopsis

The remote OT asset is affected by a vulnerability.

Description

In the Linux kernel, the following vulnerability has been resolved:

wifi: ath5k: do not access array OOB

Vincent reports:
> The ath5k driver seems to do an array-index-out-of-bounds access as > shown by the UBSAN kernel message:
> UBSAN: array-index-out-of-bounds in drivers/net/wireless/ath/ath5k/base.c:1741:20 > index 4 is out of range for type 'ieee80211_tx_rate [4]' > ...
> Call Trace:
> <TASK> > dump_stack_lvl+0x5d/0x80 > ubsan_epilogue+0x5/0x2b > __ubsan_handle_out_of_bounds.cold+0x46/0x4b > ath5k_tasklet_tx+0x4e0/0x560 [ath5k] > tasklet_action_common+0xb5/0x1c0

It is real. 'ts->ts_final_idx' can be 3 on 5212, so:
info->status.rates[ts->ts_final_idx + 1].idx = -1;
with the array defined as:
struct ieee80211_tx_rate rates[IEEE80211_TX_MAX_RATES];
while the size is:
#define IEEE80211_TX_MAX_RATES 4 is indeed bogus.

Set this 'idx = -1' sentinel only if the array index is less than the array size. As mac80211 will not look at rates beyond the size (IEEE80211_TX_MAX_RATES).

Note: The effect of the OOB write is negligible. It just overwrites the next member of info->status, i.e. ack_signal.

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

https://cert-portal.siemens.com/productcert/html/ssa-784472.html

Plugin Details

Severity: High

ID: 506380

File Name: tenable_ot_siemens_CVE-2026-46307.nasl

Version: 1.2

Type: Remote

Family: Tenable.ot

Published: 10/20/2026

Updated: 10/21/2026

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Medium

Score: 4.5

Percentile: 57.62

CVSS v2

Risk Factor: High

Base Score: 8

Temporal Score: 5.9

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

CVSS Score Source: CVE-2026-46307

CVSS v3

Risk Factor: High

Base Score: 8.3

Temporal Score: 7.2

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

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

Vulnerability Information

CPE: cpe:/o:siemens:simatic_s7-1500_tm_mfp

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 10/13/2026

Vulnerability Publication Date: 10/13/2026

Reference Information

CVE: CVE-2026-46307

CWE: 20