CRITICAL
CVE-2011-4861
CWE-264Published: December 17, 2011· Updated: Jun 16, 2026
10.0
CVSS v3.1
Official Description
The modbus_125_handler function in the Schneider Electric Quantum Ethernet Module on the NOE 771 device (aka the Quantum 140NOE771* module) allows remote attackers to install arbitrary firmware updates via a MODBUS 125 function code to TCP port 502.
Technical Analysis
CVE-2011-4861 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.
User Interaction
Scope
Impact
ConfidentialityC
IntegrityC
AvailabilityC
AV:N/AC:L/Au:N/C:C/I:C/A:C
Affected Vendors & Products
schneider-electric3 product(s)
quantum ethernet module 140noe77100quantum ethernet module 140noe77101quantum ethernet module 140noe77111
Source: NVD CPE · 3 total CPE entries
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
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GitHub PoC Search
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Rapid7 / Metasploit
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PacketStorm
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NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
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All References (2)
Quick Facts
CVE IDCVE-2011-4861
CVSS Score10.0 / 10
SeverityCRITICAL
WeaknessCWE-264
CISA KEVNo
Affected1 vendor(s)
PublishedDec 17, 2011
Related CVEs (CWE-264)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2011-4861 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.