CVE-2018-4850 Denial of service in SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and below, SIMATIC S7-400 (incl. F) CPU hardware version 5.0, SIMATIC S7-400H CPU hardware version 4.5 and below
Improper validation of S7 communication packets allows attackers to cause a Denial-of-Service condition on Siemens SIMATIC S7-400 CPUs.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2018-4850?
CVE-2018-4850 is a high-severity denial of service vulnerability in Siemens AG SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and below, SIMATIC S7-400 (incl. F) CPU hardware version 5.0, SIMATIC S7-400H CPU hardware version 4.5 and below, published on 16 May 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A vulnerability has been identified in SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and below (All versions), SIMATIC S7-400 (incl. F) CPU hardware version 5.0 (All firmware versions < V5.2), SIMATIC S7-400H CPU hardware version 4.5 and below (All versions). The affected CPUs improperly validate S7 communication packets which could cause a Denial-of-Service condition of the CPU. The CPU will remain in DEFECT mode until manual restart.
Weakness: CWE-20
Which versions are affected by CVE-2018-4850?
It affects 2 products.
Products include Siemens Simatic S7-400 Firmware, Siemens Simatic S7-400h Firmware.
How do I fix CVE-2018-4850?
No fix has been published for CVE-2018-4850 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2018-4850 being exploited?
There is no known exploitation of CVE-2018-4850 in the wild and no public exploit code.
Other vulnerabilities in Siemens AG SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and below, SIMATIC S7-400 (incl. F) CPU hardware version 5.0, SIMATIC S7-400H CPU hardware version 4.5 and below
Sources
Also known as GHSA-9c5r-829c-7rjc.