CVE-2011-20001: Input Validation Flaw (CVSS 7.5)

Description

A vulnerability has been identified in SIMATIC S7-1200 CPU V1 family (incl. SIPLUS variants) (All versions < V2.0.3), SIMATIC S7-1200 CPU V2 family (incl. SIPLUS variants) (All versions < V2.0.3). The web server interface of affected devices improperly processes incoming malformed HTTP traffic at high rate. This could allow an unauthenticated remote attacker to force the device entering the stop/defect state, thus creating a denial of service condition.

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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-20 Improper Input Validation

References

Other References

https://cert-portal.siemens.com/productcert/html/ssa-625789.html

Frequently Asked Questions

What is CVE-2011-20001? +

A vulnerability has been identified in SIMATIC S7-1200 CPU V1 family (incl. SIPLUS variants) (All versions < V2.0.3), SIMATIC S7-1200 CPU V2 family (incl. SIPLUS variants) (All versions < V2.0.3). The web server interface of affected devices improperly processes incoming malformed HTTP traffic at high rate. This could allow an unauthenticated remote attacker to force the device entering the stop/defect state, thus creating a denial of service condition. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2011-20001? +

CVE-2011-20001 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.

How do I check if I'm vulnerable to CVE-2011-20001? +

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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