CVE-2023-30756: Null Dereference (CVSS 5.9)

Description

A vulnerability has been identified in SIMATIC CP 1242-7 V2 (incl. SIPLUS variants) (All versions < V3.5.20), SIMATIC CP 1243-1 (incl. SIPLUS variants) (All versions < V3.5.20), SIMATIC CP 1243-1 DNP3 (incl. SIPLUS variants) (All versions < V3.5.20), SIMATIC CP 1243-1 IEC (incl. SIPLUS variants) (All versions < V3.5.20), SIMATIC CP 1243-7 LTE (All versions < V3.5.20), SIMATIC CP 1243-8 IRC (6GK7243-8RX30-0XE0) (All versions < V3.5.20), SIMATIC HMI Comfort Panels (incl. SIPLUS variants) (All versions), SIMATIC IPC DiagBase (All versions), SIMATIC IPC DiagMonitor (All versions), SIMATIC WinCC Runtime Advanced (All versions), SIPLUS TIM 1531 IRC (6AG1543-1MX00-7XE0) (All versions < V2.4.8), TIM 1531 IRC (6GK7543-1MX00-0XE0) (All versions < V2.4.8). The web server of the affected devices do not properly handle certain errors when using the Expect HTTP request header, resulting in NULL dereference. This could allow a remote attacker with no privileges to cause a denial of service condition in the system.

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CVSS v3.1 Score

5.9

MEDIUM

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

Weakness Type (CWE)

CWE-476 CWE-476

References

Other References

https://cert-portal.siemens.com/productcert/html/ssa-423808.html

Frequently Asked Questions

What is CVE-2023-30756? +

A vulnerability has been identified in SIMATIC CP 1242-7 V2 (incl. SIPLUS variants) (All versions < V3.5.20), SIMATIC CP 1243-1 (incl. SIPLUS variants) (All versions < V3.5.20), SIMATIC CP 1243-1 DNP3 (incl. SIPLUS variants) (All versions < V3.5.20), SIMATIC CP 1243-1 IEC (incl. SIPLUS variants) (All versions < V3.5.20), SIMATIC CP 1243-7 LTE (All versions < V3.5.20), SIMATIC CP 1243-8 IRC (6GK7243-8RX30-0XE0) (All versions < V3.5.20), SIMATIC HMI Comfort Panels (incl. SIPLUS variants) (All versions), SIMATIC IPC DiagBase (All versions), SIMATIC IPC DiagMonitor (All versions), SIMATIC WinCC Runtime Advanced (All versions), SIPLUS TIM 1531 IRC (6AG1543-1MX00-7XE0) (All versions < V2.4.8), TIM 1531 IRC (6GK7543-1MX00-0XE0) (All versions < V2.4.8). The web server of the affected devices do not properly handle certain errors when using the Expect HTTP request header, resulting in NULL dereference. This could allow a remote attacker with no privileges to cause a denial of service condition in the system. It has a CVSS v3.1 base score of 5.9 (MEDIUM).

How severe is CVE-2023-30756? +

CVE-2023-30756 has a CVSS v3.1 score of 5.9 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

How do I check if I'm vulnerable to CVE-2023-30756? +

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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