Skip to content
Noroxi
CVE-2020-7540· NVD / CVE Program· CNA schneider

A CWE-306: Missing Authentication for Critical Function vulnerability exists in the Web Server on Modicon M340, Legacy Offers Modicon Quantu

Noroxi assessment

Priority: Plan (action score 40/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 2.3% (FIRST EPSS); higher than 83.1% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to the record, no fixed version is available yet.

Add it to your regular patch cycle. Update when a fix is released; follow the vendor's advisory.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

A CWE-306: Missing Authentication for Critical Function vulnerability exists in the Web Server on Modicon M340, Legacy Offers Modicon Quantum and Modicon Premium and associated Communication Modules (see security notification for affected versions), that could cause unauthenticated command execution in the controller when sending special HTTP requests.

CriticalCVSS 9.8 · v3.1—No exploit No fix recorded
Published
Dec 10, 2020
Updated
Jun 16, 2026
EPSS
2.3% · 83th percentile

Report tools

JSON

Action score

40

Plan

Add it to your regular patch cycle.

CVSS
39 / 40 · 9.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
1 / 30 · 2.3%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2020-7540

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

Your free account also gets you

Running WordPress? Scan your site free with WP Lens

  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every MondayDon't want an account? RSS feed for schneider-electric records

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

We use this product, ask for help

Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
schneider-electric140noc78000 firmware
schneider-electricmodicon m340 bmxp341000 firmware
schneider-electricmodicon m340 bmxp341000
schneider-electricmodicon m340 bmxp342000 firmware
schneider-electricmodicon m340 bmxp342000
schneider-electricmodicon m340 bmxp3420102 firmware
schneider-electricmodicon m340 bmxp3420102
schneider-electricmodicon m340 bmxp3420102cl firmware
schneider-electricmodicon m340 bmxp3420102cl
schneider-electricmodicon m340 bmxp342020 firmware
schneider-electricmodicon m340 bmxp342020
schneider-electricmodicon m340 bmxp3420302 firmware

and 34 more

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • schneider-electric 140cpu65150 firmwarebefore 6.1
  • schneider-electric 140cpu65160 firmwarebefore 6.1
  • schneider-electric 140noc77101 firmwarebefore 1.08
  • schneider-electric 140noc78000 firmwarebefore 1.74
  • schneider-electric 140noc78100 firmwarebefore 1.74
  • schneider-electric 140noe77101 firmwarebefore 7.1
  • schneider-electric 140noe77111 firmwarebefore 7.1
  • schneider-electric bmxnoc0401 firmwarebefore 2.10
  • schneider-electric bmxnoe0100 firmwarebefore 3.3
  • schneider-electric bmxnoe0110 firmwarebefore 6.5
  • schneider-electric bmxnor200h firmwareall versions
  • schneider-electric modicon m340 bmxp341000 firmwarebefore 3.30
  • schneider-electric modicon m340 bmxp342000 firmwarebefore 3.30
  • schneider-electric modicon m340 bmxp3420102 firmwarebefore 3.30
  • schneider-electric modicon m340 bmxp3420102cl firmwarebefore 3.30
  • schneider-electric modicon m340 bmxp342020 firmwarebefore 3.30
  • schneider-electric modicon m340 bmxp3420302 firmwarebefore 3.30
  • schneider-electric modicon m340 bmxp3420302cl firmwarebefore 3.30
  • schneider-electric tsxety4103 firmwarebefore 6.2
  • schneider-electric tsxety5103 firmwarebefore 6.4

Versions reported by the vendor

Affected version ranges reported by the assigning authority (schneider). Independent of NVD's CPE analysis and usually ahead of it.

  • n/a Web Server on Modicon M340, Legacy Offers Modicon Quantum and Modicon Premium and associated Communication Modules (see security notification for affected versions)

    • Web Server on Modicon M340, Legacy Offers Modicon Quantum and Modicon Premium and associated Communication Modules (see security notification for affected versions)affected

Same product

schneider-electric: all records

Other highest-scoring records for the same primary product.

  • CVE-2023-6408 CWE-924: Improper Enforcement of Message Integrity During Transmission in a Communication Channel vulnerability exists that could cause a d
    32Monitor
  • CVE-2021-22786A CWE-200: Information Exposure vulnerability exists that could cause the exposure of sensitive information stored on the memory of the cont
    30Monitor
  • CVE-2022-0222A CWE-269: Improper Privilege Management vulnerability exists that could cause a denial of service of the Ethernet communication of the cont
    30Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2020-7536Dec 10, 2020 · A CWE-754:Improper Check for Unusual or Exceptional Conditions vulnerability exists in Modicon M340 CPUs (BMXP34* versions prior to V3.30) M
    30Monitor
  • ← EarlierCVE-2020-7539Dec 10, 2020 · A CWE-754 Improper Check for Unusual or Exceptional Conditions vulnerability exists in the Web Server on Modicon M340, Legacy Offers Modicon
    30Monitor
  • Later →CVE-2020-7541Dec 10, 2020 · A CWE-425: Direct Request ('Forced Browsing') vulnerability exists in the Web Server on Modicon M340, Legacy Offers Modicon Quantum and Modi
    21Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-306 · Missing Authentication for Critical Function

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Root cause

A function added for development or support ships to production without authentication. It often relies on the assumption that it is “only reachable from the internal network.”

The bug in code

The whole CWE-306 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

ts
// Added for the support teamapp.post("/maintenance/reset", resetDevice);

Fixed

ts
if (config.maintenanceEnabled) {  app.post(    "/maintenance/reset",    requireSession, requireRole("admin"), resetDevice  );}

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

ATT&CK techniques

—

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records