CVE-2023-51440: simatic cp 343-1 — Fix

Description

A vulnerability has been identified in SIMATIC CP 343-1 (6GK7343-1EX30-0XE0) (All versions), SIMATIC CP 343-1 Lean (6GK7343-1CX10-0XE0) (All versions), SIPLUS NET CP 343-1 (6AG1343-1EX30-7XE0) (All versions), SIPLUS NET CP 343-1 Lean (6AG1343-1CX10-2XE0) (All versions). Affected products incorrectly validate TCP sequence numbers. This could allow an unauthenticated remote attacker to create a denial of service condition by injecting spoofed TCP RST packets.

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CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-940 CWE-940

Affected Products

Vendor	Product	Versions
siemens	simatic_cp_343-1	All
siemens	simatic_cp_343-1_firmware	All
siemens	simatic_cp_343-1_lean	All
siemens	simatic_cp_343-1_lean_firmware	All
siemens	siplus_net_cp_343-1	All
siemens	siplus_net_cp_343-1_firmware	All
siemens	siplus_net_cp_343-1_lean	All
siemens	siplus_net_cp_343-1_lean_firmware	All

References

Advisories & Patches

https://cert-portal.siemens.com/productcert/html/ssa-516818.html https://cert-portal.siemens.com/productcert/html/ssa-516818.html

Frequently Asked Questions

What is CVE-2023-51440? +

A vulnerability has been identified in SIMATIC CP 343-1 (6GK7343-1EX30-0XE0) (All versions), SIMATIC CP 343-1 Lean (6GK7343-1CX10-0XE0) (All versions), SIPLUS NET CP 343-1 (6AG1343-1EX30-7XE0) (All versions), SIPLUS NET CP 343-1 Lean (6AG1343-1CX10-2XE0) (All versions). Affected products incorrectly validate TCP sequence numbers. This could allow an unauthenticated remote attacker to create a denial of service condition by injecting spoofed TCP RST packets. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2023-51440? +

CVE-2023-51440 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2023-51440? +

CVE-2023-51440 affects products from siemens, specifically: simatic_cp_343-1, simatic_cp_343-1_firmware, simatic_cp_343-1_lean, simatic_cp_343-1_lean_firmware, siplus_net_cp_343-1, siplus_net_cp_343-1_firmware, siplus_net_cp_343-1_lean, siplus_net_cp_343-1_lean_firmware. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-51440? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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