How severe is CVE-2023-30756?

CVE-2023-30756 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-30756 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2023-30756?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2023-30756 have an EU (EUVD) identifier?

Yes. CVE-2023-30756 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-35120.

When was CVE-2023-30756 published?

CVE-2023-30756 was published on 2024-09-10 and last updated on 2026-06-17.

CVE-2023-30756

CVE-2023-30756 is a medium-severity vulnerability with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-476.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v4: 8.2
EPSS exploit prediction: 0% (36th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2023-35120
Weakness: CWE-476
Published: 2024-09-10
Last modified: 2026-06-17

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.

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.
How severe is CVE-2023-30756?: CVE-2023-30756 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-30756 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2023-30756?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2023-30756 have an EU (EUVD) identifier?: Yes. CVE-2023-30756 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-35120.
When was CVE-2023-30756 published?: CVE-2023-30756 was published on 2024-09-10 and last updated on 2026-06-17.

References

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

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