CVE-2025-40820

published 2025-12-09

CVE-2025-40820: Affected products do not properly enforce TCP sequence number validation in specific scenarios but accept values within a broad range. This could allow an…

high 8.7 CVSS 4.0

AV N AC L AT N PR N UI N VC N VI N VA H SC N SI N SA N E X CR X IR X AR X MAV X MAC X MAT X MPR X MUI X MVC X MVI X MVA X MSC X MSI X MSA X S X AU X R X V X RE X U X

Affected products do not properly enforce TCP sequence number validation in specific scenarios but accept values within a broad range. This could allow an unauthenticated remote attacker e.g. to interfere with connection setup, potentially leading to a denial of service. The attack succeeds only if an attacker can inject IP packets with spoofed addresses at precisely timed moments, and it affects only TCP-based services.

Affected

132 ranges · showing 25

Vendor	Product	Version range	Fixed in
siemens	sidoor_atd430w	< *	*
siemens	sidoor_ate530g_coated	< *	*
siemens	sidoor_ate530s_coated	< *	*
siemens	simatic_cfu_diq	< V2.0.0	V2.0.0
siemens	simatic_cfu_pa	< V2.0.0	V2.0.0
siemens	simatic_et_200al_im_157-1_pn	< *	*
siemens	simatic_et_200mp_im_155-5_pn_hf	>= V4.2.0 < *	*
siemens	simatic_et_200pro_im_154-8_pn_dp_cpu	< *	*
siemens	simatic_et_200pro_im_154-8f_pn_dp_cpu	< *	*
siemens	simatic_et_200pro_im_154-8fx_pn_dp_cpu	< *	*
siemens	simatic_et_200s_im_151-8_pn_dp_cpu	< *	*
siemens	simatic_et_200s_im_151-8f_pn_dp_cpu	< *	*
siemens	simatic_et_200sp_cpu_1510sp-1_pn	< *	*
siemens	simatic_et_200sp_cpu_1510sp_f-1_pn	< *	*
siemens	simatic_et_200sp_cpu_1512sp-1_pn	< *	*
siemens	simatic_et_200sp_cpu_1512sp_f-1_pn	< *	*
siemens	simatic_et_200sp_im_155-6_mf_hf	< *	*
siemens	simatic_et_200sp_im_155-6_pn_2_hf	>= V4.2.0 < *	*
siemens	simatic_et_200sp_im_155-6_pn_3_hf	>= V4.2.0 < *	*
siemens	simatic_et_200sp_im_155-6_pn_ha	< V1.3	V1.3
siemens	simatic_et_200sp_im_155-6_pn_hf	>= V4.2.0 < *	*
siemens	simatic_pn_mf_coupler	< *	*
siemens	simatic_pn_pn_coupler	< V6.0.0	V6.0.0
siemens	simatic_s7-1200_cpu_1211c_ac_dc_rly	< V4.4.0	V4.4.0
siemens	simatic_s7-1200_cpu_1211c_dc_dc_dc	< V4.4.0	V4.4.0

CWE-940