NVD / CVE Program· CNA mitre

CVE-2020-13238: Mitsubishi MELSEC iQ-R Series PLCs with firmware 33 allow attackers to halt the industrial process by sending an unauthenticated crafted…

HighCVSS 7.5 · v3.1—No exploit No fix recorded

Noroxi assessment

Priority: Monitor (action score 31/100)

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: 3.4% (FIRST EPSS); higher than 89% 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.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. 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

Mitsubishi MELSEC iQ-R Series PLCs with firmware 33 allow attackers to halt the industrial process by sending an unauthenticated crafted packet over the network, because this denial of service attack consumes excessive CPU time. After halting, physical access to the PLC is required in order to restore production.

Published: Jun 10, 2020
Updated: Jun 16, 2026
EPSS: 3.4% · 89th percentile
CWE: CWE-400

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 30 / 40 · 7.5 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 1 / 30 · 3.4%

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.

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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.

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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.

Vendor	Product	CPE
mitsubishielectric	melsec iq-r00cpu firmware	cpe:2.3:o:mitsubishielectric:melsec_iq-r00cpu_firmware
mitsubishielectric	melsec iq-r00cpu	cpe:2.3:h:mitsubishielectric:melsec_iq-r00cpu
mitsubishielectric	melsec iq-r01cpu firmware	cpe:2.3:o:mitsubishielectric:melsec_iq-r01cpu_firmware
mitsubishielectric	melsec iq-r01cpu	cpe:2.3:h:mitsubishielectric:melsec_iq-r01cpu
mitsubishielectric	melsec iq-r02cpu firmware	cpe:2.3:o:mitsubishielectric:melsec_iq-r02cpu_firmware
mitsubishielectric	melsec iq-r02cpu	cpe:2.3:h:mitsubishielectric:melsec_iq-r02cpu
mitsubishielectric	melsec iq-r04cpu firmware	cpe:2.3:o:mitsubishielectric:melsec_iq-r04cpu_firmware
mitsubishielectric	melsec iq-r04cpu	cpe:2.3:h:mitsubishielectric:melsec_iq-r04cpu
mitsubishielectric	melsec iq-r08cpu firmware	cpe:2.3:o:mitsubishielectric:melsec_iq-r08cpu_firmware
mitsubishielectric	melsec iq-r08cpu	cpe:2.3:h:mitsubishielectric:melsec_iq-r08cpu
mitsubishielectric	melsec iq-r16cpu firmware	cpe:2.3:o:mitsubishielectric:melsec_iq-r16cpu_firmware
mitsubishielectric	melsec iq-r16cpu	cpe:2.3:h:mitsubishielectric:melsec_iq-r16cpu

and 30 more

Affected versions

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

mitsubishielectric melsec iq-r00cpu firmwareup to 7 inclusive
mitsubishielectric melsec iq-r01cpu firmwareup to 7 inclusive
mitsubishielectric melsec iq-r02cpu firmwareup to 7 inclusive
mitsubishielectric melsec iq-r04cpu firmwareup to 39 inclusive
mitsubishielectric melsec iq-r08cpu firmwareup to 39 inclusive
mitsubishielectric melsec iq-r08fcpu firmwareup to 20 inclusive
mitsubishielectric melsec iq-r08pcpu firmwareall versions
mitsubishielectric melsec iq-r08sfcpu firmwareall versions
mitsubishielectric melsec iq-r120cpu firmwareup to 39 inclusive
mitsubishielectric melsec iq-r120fcpu firmwareup to 20 inclusive
mitsubishielectric melsec iq-r120pcpu firmwareall versions
mitsubishielectric melsec iq-r120sfcpu firmwareall versions
mitsubishielectric melsec iq-r16cpu firmwareup to 39 inclusive
mitsubishielectric melsec iq-r16fcpu firmwareup to 20 inclusive
mitsubishielectric melsec iq-r16pcpu firmwareall versions
mitsubishielectric melsec iq-r16sfcpu firmwareall versions
mitsubishielectric melsec iq-r32cpu firmwareup to 39 inclusive
mitsubishielectric melsec iq-r32fcpu firmwareup to 20 inclusive
mitsubishielectric melsec iq-r32pcpu firmwareall versions
mitsubishielectric melsec iq-r32sfcpu firmwareall versions

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.

No history yet (it accumulates with the daily EPSS job).

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).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

TR-20-920 · Nov 6, 2020(Mitsubishi Electric Ürünleri Zafiyeti)

All national notices →

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: none
Integrity: none
Availability: high · the service can be disrupted

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: None
Scope: Unchanged
Confidentiality impact: None
Integrity impact: None
Availability impact: High

Weakness class (CWE)

CWE-400 · Uncontrolled Resource Consumption

CVSS vector

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

nvd-primary

Root cause

Code that parses nested structures sets no depth or size limit. A small input can turn into a disproportionate processing load.

The bug in code

The whole CWE-400 class

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

Vulnerable

1function expand(node) {
2  return node.children.map(expand);
3}

Fixed

1const MAX_DEPTH = 32;
2function expand(node, depth = 0) {
3  if (depth > MAX_DEPTH) throw new Error("too deep");
4  return node.children.map((c) => expand(c, depth + 1));
5}

Attack context

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

Attack patterns (CAPEC)

ATT&CK techniques

Endpoint Denial of ServiceT1499

Change log

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

References

jvn.jp/vu/JVNVU97662844/index.html

Show all references (2 more)

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

All records