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Fencer Intel
high 7.5

CVE-2011-20001 json

A vulnerability has been identified in SIMATIC S7-1200 CPU V1 family (incl.

published 2025-10-14 12 mo ago modified 2026-06-16 4 mo ago also EUVD-2011-5262

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 40%
public exploits
0
none known

Summary

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.

Patch / fix

  • Siemens SIMATIC S7-1200 CPU V1 family (incl. SIPLUS variants) V2.0.3
  • Siemens SIMATIC S7-1200 CPU V2 family (incl. SIPLUS variants) V2.0.3

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-25-294-03 updated cvss 7.5

Siemens SIMATIC S7-1200 CPU V1/V2 Devices

  • Siemens SIMATIC S7-1200 CPU V1 family (incl. SIPLUS variants) < 2.0.3 Siemens SIMATIC S7-1200 CPU V2 family (incl. SIPLUS variants) < 2.0.3
    affected: fixed in V2.0.3, mitigation

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
12 mo ago

Exploit prediction

0.47% chance of exploitation in the next 30 days, higher than 40% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA 4.0 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CNA 4.0 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

  • Siemens SIMATIC S7-1200 CPU V1 family (incl. SIPLUS variants)
  • Siemens SIMATIC S7-1200 CPU V2 family (incl. SIPLUS variants)

Classification

Weakness
  • CWE-20 Improper Input Validation

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.